10/30/09
Costumes! Costumes! Costumes!
I was great to see so many people get in the spirit and dress up for Halloween. Try not to eat too much candy this weekend nor spook too many little kids...(a few is fine, though)
Honors Physics and both Physics sections underwent their painful examination process. Monday we begin the momentum unit!
Physical Science B discussed pressure variations with depth in a fluid. For the same area of object, with increasing depth comes an increased force (weight) due to the greater amount of water on top of the object. The lab that you will conduct on Monday will allow you to investigate this phenomenon more thoroughly, so make sure that you have read over the lab instructions and completed your practice problems in preparation. CLICK HERE for a copy of your pressure and depth worksheet and solutions key.
Physical Science E examined Pascal's Principle and how it can be used to design hydraulic devices. It seemed like people were getting the hang of solving hydraulics problems, so I'm confident you will do a good job with them over the weekend. CLICK HERE for a copy of your pressure worksheet and solutions key. We'll go over them on Monday and begin to discuss the topic of your last lab - pressure variations with depth.
Homework
Honors Physics A: 6B, 6C #1 and #6, 9 and 16 of the Chapter Review
Physical Science B: Read lab sheet and complete pressure and depth worksheet
Physical Science E: Complete Pascal's Principle worksheet
Physics F and G: 6A #1 and 2, 6B #1 and p. 232 #1-3, 6
Honors Physics and both Physics sections underwent their painful examination process. Monday we begin the momentum unit!
Physical Science B discussed pressure variations with depth in a fluid. For the same area of object, with increasing depth comes an increased force (weight) due to the greater amount of water on top of the object. The lab that you will conduct on Monday will allow you to investigate this phenomenon more thoroughly, so make sure that you have read over the lab instructions and completed your practice problems in preparation. CLICK HERE for a copy of your pressure and depth worksheet and solutions key.
Physical Science E examined Pascal's Principle and how it can be used to design hydraulic devices. It seemed like people were getting the hang of solving hydraulics problems, so I'm confident you will do a good job with them over the weekend. CLICK HERE for a copy of your pressure worksheet and solutions key. We'll go over them on Monday and begin to discuss the topic of your last lab - pressure variations with depth.
Homework
Honors Physics A: 6B, 6C #1 and #6, 9 and 16 of the Chapter Review
Physical Science B: Read lab sheet and complete pressure and depth worksheet
Physical Science E: Complete Pascal's Principle worksheet
Physics F and G: 6A #1 and 2, 6B #1 and p. 232 #1-3, 6
Bracing for Tests
Honors Physics had the chance to go over their homework for the Power section of the chapter and used the remainder of the class to review for tomorrow’s exam. As usual, we walked through the chapter highlighting concepts and skills and took time to address questions people had about the material or the problem-solving techniques. Monday, we begin our unit on momentum.
Physical Science B went over their Chapter 11 exams and then discussed Pascal’s principle and the function of hydraulic devices. Hydraulic devices multiply our effort force, so that we can successfully work against a resistance larger than what we could work against alone. We’ll go over the homework problems tomorrow and work a few additional ones to make sure that people have a good grasp of the math. Then, we begin to discuss how the force of gravity affects pressure in fluids and that will lead us into Monday’s lab which targets this idea specifically.
Physical Science E reviewed yesterday’s lab and began a discussion of how forces are generated within fluids (which then leads to pressure generation in fluids). We then tuned to the idea that fluids move “down” pressure gradients – they move from areas of higher pressure to areas of lower pressure. This can have an impact on any matter that stands in the path of the moving fluid and we discussed the implications for living and physical systems subject to pressure imbalances. Tomorrow, we’ll take up a discussion of what happens to fluids when they aren’t allowed to move to a lower pressure area when the pressure in one area of the fluid experiences an increase. The transmission of pressure by a fluid, equally and in all directions, has practical applications that we will investigate with a study of hydraulic devices.
Physics F and G reviewed for tomorrow’s exam. We went back through the chapter and worked through any problems or questions that people had about the material. You can rest assured that there won’t be any problems on the test like #34 of the Chapter Review, but you should be able to perform simple calculations for work, kinetic energy (and the work-kinetic energy theorem), both potential energies, energy conservation and power. If you have any additional questions, stop in tomorrow morning before school and we can address them at that time. On Monday, we will extend our discussion of forces and energy to the concept of momentum and its conservation.
Homework
Honors Physics A, Physics F and G: Study for exam
Physical Science B: p. 96 #26-28
Physical Science E: None
Physical Science B went over their Chapter 11 exams and then discussed Pascal’s principle and the function of hydraulic devices. Hydraulic devices multiply our effort force, so that we can successfully work against a resistance larger than what we could work against alone. We’ll go over the homework problems tomorrow and work a few additional ones to make sure that people have a good grasp of the math. Then, we begin to discuss how the force of gravity affects pressure in fluids and that will lead us into Monday’s lab which targets this idea specifically.
Physical Science E reviewed yesterday’s lab and began a discussion of how forces are generated within fluids (which then leads to pressure generation in fluids). We then tuned to the idea that fluids move “down” pressure gradients – they move from areas of higher pressure to areas of lower pressure. This can have an impact on any matter that stands in the path of the moving fluid and we discussed the implications for living and physical systems subject to pressure imbalances. Tomorrow, we’ll take up a discussion of what happens to fluids when they aren’t allowed to move to a lower pressure area when the pressure in one area of the fluid experiences an increase. The transmission of pressure by a fluid, equally and in all directions, has practical applications that we will investigate with a study of hydraulic devices.
Physics F and G reviewed for tomorrow’s exam. We went back through the chapter and worked through any problems or questions that people had about the material. You can rest assured that there won’t be any problems on the test like #34 of the Chapter Review, but you should be able to perform simple calculations for work, kinetic energy (and the work-kinetic energy theorem), both potential energies, energy conservation and power. If you have any additional questions, stop in tomorrow morning before school and we can address them at that time. On Monday, we will extend our discussion of forces and energy to the concept of momentum and its conservation.
Homework
Honors Physics A, Physics F and G: Study for exam
Physical Science B: p. 96 #26-28
Physical Science E: None
10/28/09
Wet Wednesday
Honors Physics completed the work and energy unit with a discussion of energy conservation and power. As you work problems with energy conservation, remember to take into account all forms of mechanical energy present at the beginning and end of the situation in question. Also, if elastic potential energy is in the picture, you can’t cancel out mass in the way you can when only kinetic energy and gravitational potential energy are involved. It also pays to take time to look at a problem wearing your force/kinematics hat, as well as your work/energy hat. Consider how you would describe or explain a situation using forces and kinematics and see how that description/explanation can also be matched by using work and energy concepts. When you get to the power problems, you need to reflect on the variety of ways that we can express work – force x distance, change in energy, etc. – to see how best to approach the power issue. Also, don’t forget the force x velocity derivation. That can come in handy in certain situations. Tomorrow, exam review. Friday, exam.
Physical Science B began their study of forces in fluids today with a discussion of pressure. Make sure that you are clear about the difference between force and pressure and how manipulating force and area create different pressure situations. We then turned towards the tendency of fluids to move from areas of high pressure to areas of low pressure and the implication this motion has for matter that lies in a fluid’s path. We discussed breathing, drinking from a straw, vacuum-cleaner function and hazards of traveling in space without a pressure suit. Tomorrow, we take up the possibility that fluids are blocked from motion – what happens if you apply pressure to one part of a fluid, but don’t allow the fluid to move? Think hydraulics…
Physical Science E had a wet and wild lab experience. The pressure change in a water column due to depth was investigated and, despite a few floods, data for all groups was great. A clear linear relationship between pressure and depth was witnessed: with greater depth comes greater pressure. The same trend exists in all fluids, including the atmosphere. The pressure is highest at sea level and decreases with altitude. The types of problems you worked at the end of the lab are typical of those that scientists and engineers use when they are designing equipment or experiments to work at a certain depth in an ocean or lake or at a height in the atmosphere. Tomorrow, we’ll review the lab and begin discussing the source of pressure in fluids.
Physics F and G discussed power and cleared up some misconceptions about the concept of power. We took time to complete going over all the previous homework problems and that will lead us into our exam review tomorrow. Look over the chapter tonight and come with any and all questions for exam preparation.
Homework
Honors Physics A: Complete Practice 5F #1,2 and p. 195 #33-36
Physical Science B: None
Physical Science E: Complete lab write up
Physics F: Complete 5.4 Section Review
Physics G: Study for exam
Physical Science B began their study of forces in fluids today with a discussion of pressure. Make sure that you are clear about the difference between force and pressure and how manipulating force and area create different pressure situations. We then turned towards the tendency of fluids to move from areas of high pressure to areas of low pressure and the implication this motion has for matter that lies in a fluid’s path. We discussed breathing, drinking from a straw, vacuum-cleaner function and hazards of traveling in space without a pressure suit. Tomorrow, we take up the possibility that fluids are blocked from motion – what happens if you apply pressure to one part of a fluid, but don’t allow the fluid to move? Think hydraulics…
Physical Science E had a wet and wild lab experience. The pressure change in a water column due to depth was investigated and, despite a few floods, data for all groups was great. A clear linear relationship between pressure and depth was witnessed: with greater depth comes greater pressure. The same trend exists in all fluids, including the atmosphere. The pressure is highest at sea level and decreases with altitude. The types of problems you worked at the end of the lab are typical of those that scientists and engineers use when they are designing equipment or experiments to work at a certain depth in an ocean or lake or at a height in the atmosphere. Tomorrow, we’ll review the lab and begin discussing the source of pressure in fluids.
Physics F and G discussed power and cleared up some misconceptions about the concept of power. We took time to complete going over all the previous homework problems and that will lead us into our exam review tomorrow. Look over the chapter tonight and come with any and all questions for exam preparation.
Homework
Honors Physics A: Complete Practice 5F #1,2 and p. 195 #33-36
Physical Science B: None
Physical Science E: Complete lab write up
Physics F: Complete 5.4 Section Review
Physics G: Study for exam
10/27/09
Tuesday is SnoozeDay
Leave work, get dogs from daycare, feed said dogs on return home, flop on couch and take nap. That is my plan and I'm sticking to it...
Honors Physics, although sparsely populated due to the Mathematics Field Day trip, discussed elastic potential energy and reviewed the homework problems for the work-kinetic theorem, gravitational potential energy and elastic potential energy. Tomorrow we will draw these together and discuss conservation of mechanical energy, so be ready to think back to your lab activity as it will be used as an example of energy conservation. We should also have time to discuss power, the rate at which work is done or energy is converted. Exam looks like it will fall on Friday, not next week, so time budget accordingly.
Physical Science B and E took their exam on forces and momentum. Tomorrow, we jump back in the book to attack how forces and involved with fluid systems. We’ll look at liquids and gases, discussing such topics as buoyancy, pressure, the gas laws and density. Tomorrow, B Block will begin a discussion of buoyancy and Archimedes Principle. E Block will engage in a lab activity that will allow students to study the pressure changes with depth in a water column. We will make some modifications to the apparatus, owing to the fact that the caps I bought to fit the acrylic piping don’t fit (even though the nice man at the hardware store said they would), so make sure to pay close attention to the pre-lab overview to correct assemble your experiment.
Physics F worked on their conservation of energy in simple harmonic motion lab. Our discussion yesterday gave you some ammunition for the preliminary questions and for the analysis of the graphs of displacement, velocity, kinetic energy, elastic potential energy and total energy over time. Reflect on this material when you pull together your conclusion for the lab synopsis.
Physics G discussed conservation of energy, with special emphasis on conservation of mechanical energy. With the presence of friction, the conversion between kinetic and potential energy is not absolute. Some energy is always tuned to the nonmechanical form of heat. However, in low-friction situations, the loss of mechanical energy is sufficiently low that conservation of mechanical energy can be used to make predictive calculations. Tomorrow, we discuss power and begin reviewing for the exam on Friday.
Homework
Honors Physics: Practice 5E
Physical Science B: Read pgs. 80-86 and answer #19 on page 95
Physical Science E: Read lab sheet and pgs. 80-86. Complete #21 and #34 on page 95.
Physics F: Complete lab write up
Physics G: Read 5.4 and complete the 5.4 Section Review
Honors Physics, although sparsely populated due to the Mathematics Field Day trip, discussed elastic potential energy and reviewed the homework problems for the work-kinetic theorem, gravitational potential energy and elastic potential energy. Tomorrow we will draw these together and discuss conservation of mechanical energy, so be ready to think back to your lab activity as it will be used as an example of energy conservation. We should also have time to discuss power, the rate at which work is done or energy is converted. Exam looks like it will fall on Friday, not next week, so time budget accordingly.
Physical Science B and E took their exam on forces and momentum. Tomorrow, we jump back in the book to attack how forces and involved with fluid systems. We’ll look at liquids and gases, discussing such topics as buoyancy, pressure, the gas laws and density. Tomorrow, B Block will begin a discussion of buoyancy and Archimedes Principle. E Block will engage in a lab activity that will allow students to study the pressure changes with depth in a water column. We will make some modifications to the apparatus, owing to the fact that the caps I bought to fit the acrylic piping don’t fit (even though the nice man at the hardware store said they would), so make sure to pay close attention to the pre-lab overview to correct assemble your experiment.
Physics F worked on their conservation of energy in simple harmonic motion lab. Our discussion yesterday gave you some ammunition for the preliminary questions and for the analysis of the graphs of displacement, velocity, kinetic energy, elastic potential energy and total energy over time. Reflect on this material when you pull together your conclusion for the lab synopsis.
Physics G discussed conservation of energy, with special emphasis on conservation of mechanical energy. With the presence of friction, the conversion between kinetic and potential energy is not absolute. Some energy is always tuned to the nonmechanical form of heat. However, in low-friction situations, the loss of mechanical energy is sufficiently low that conservation of mechanical energy can be used to make predictive calculations. Tomorrow, we discuss power and begin reviewing for the exam on Friday.
Homework
Honors Physics: Practice 5E
Physical Science B: Read pgs. 80-86 and answer #19 on page 95
Physical Science E: Read lab sheet and pgs. 80-86. Complete #21 and #34 on page 95.
Physics F: Complete lab write up
Physics G: Read 5.4 and complete the 5.4 Section Review
10/26/09
The Various Faces of Energy
Honors Physics took time to discuss their conservation of energy lab and it seems that most groups got very nice results. A clear linear relationship between applied force and displacement to obtain the spring constant and clean sine functions to describe the oscillation of the mass-spring system. Energy was well conserved in the tests, with the addition of the index card demonstrating the transformation of energy to a non-conservative form (heat). We then went over the last exam and began a discussion of potential energy. We hit gravitational potential energy today and will continue on with that tomorrow, including, as well, elastic potential energy.
Physical Science B and E reviewed for their Chapter 11 exam. It still seems that a lot of folks are having trouble with the math portion. Don’t forget to ask for extra help or extra problems to work when you are having difficulty with a concept. Don’t wait until the day before the test, either. Get help as soon as you are having problems. Often, in this course, concepts reinforce each other – if you are having difficulty with one, you will likely have difficulty with others in the chapter/course.
Physics F discussed conservation of mechanical energy today. When we talk about mechanical energy, we mean kinetic energy and any forms of potential energy available. For our purposes, that will be either gravitational or elastic potential energy. In a system where friction is negligible, we expect the total amount of mechanical energy to remain constant in a system, although it can be converted repeatedly between forms/types. When friction is significant, we expect to see a reduction in the total amount of usable mechanical energy in the system. Tomorrow’s lab will allow you to see how energy is converted between potential/kinetic in a mass-spring system and how the total amount of energy changes with and without significant frictional resistance.
Physics G conducted their conservation of energy lab today and preliminary results look good. The first part of the lab allowed you to calculate the spring constant for your individual spring, which is required if we are going to assess elastic potential energy. The second part of the activity allowed you to visualize the motion of the spring through time and evaluate the energy changes associated with that motion. Simple harmonic motion exists in many oscillating systems like springs and pendulums and the plot of displacement vs. time makes a nice sine curve, like groups found for their system. As you consider your results and write the conclusion for your lab, think about what is happening in each piece of the displacement graph (in terms of both position and velocity) and why you got the pattern you witnessed for your energy plots. We will discuss your lab tomorrow and use it to illustrate our discussion of conservation of energy.
Homework
Honors Physics A: 5D and 5.2 Section Review
Physical Science B and E: Review for exam
Physics F: Read lab sheet. Complete 5.3 SR #2,3 and p. 195 #30-34 for Wednesday
Physics G: Complete lab write up. Complete 5.3 SR #2,3 and p. 195 #30-34
Physical Science B and E reviewed for their Chapter 11 exam. It still seems that a lot of folks are having trouble with the math portion. Don’t forget to ask for extra help or extra problems to work when you are having difficulty with a concept. Don’t wait until the day before the test, either. Get help as soon as you are having problems. Often, in this course, concepts reinforce each other – if you are having difficulty with one, you will likely have difficulty with others in the chapter/course.
Physics F discussed conservation of mechanical energy today. When we talk about mechanical energy, we mean kinetic energy and any forms of potential energy available. For our purposes, that will be either gravitational or elastic potential energy. In a system where friction is negligible, we expect the total amount of mechanical energy to remain constant in a system, although it can be converted repeatedly between forms/types. When friction is significant, we expect to see a reduction in the total amount of usable mechanical energy in the system. Tomorrow’s lab will allow you to see how energy is converted between potential/kinetic in a mass-spring system and how the total amount of energy changes with and without significant frictional resistance.
Physics G conducted their conservation of energy lab today and preliminary results look good. The first part of the lab allowed you to calculate the spring constant for your individual spring, which is required if we are going to assess elastic potential energy. The second part of the activity allowed you to visualize the motion of the spring through time and evaluate the energy changes associated with that motion. Simple harmonic motion exists in many oscillating systems like springs and pendulums and the plot of displacement vs. time makes a nice sine curve, like groups found for their system. As you consider your results and write the conclusion for your lab, think about what is happening in each piece of the displacement graph (in terms of both position and velocity) and why you got the pattern you witnessed for your energy plots. We will discuss your lab tomorrow and use it to illustrate our discussion of conservation of energy.
Homework
Honors Physics A: 5D and 5.2 Section Review
Physical Science B and E: Review for exam
Physics F: Read lab sheet. Complete 5.3 SR #2,3 and p. 195 #30-34 for Wednesday
Physics G: Complete lab write up. Complete 5.3 SR #2,3 and p. 195 #30-34
10/23/09
Friday Fun
Honors Physics got to play with springs during lab today, determining the spring constant and monitoring energy changes of the spring while oscillating. As potential energy decreases, kinetic energy increases and vice versa, always at the same rate, so that the total energy of the systems is conserved. For your spring constant, different groups will have different values – it is a built-in property of the spring, based on the spring’s manufacture. Plotting displacement and force produced a nice linear relationship, the slope of which was the spring constant. On Monday, have the lab ready and we will start our discussion of potential energy, including an overview of yesterday’s homework questions.
Physical Science B continued reviewing for the exam, but E Block was lost due to Peer Mentoring. Accordingly, we will have to delay the exam until Tuesday, so that E Block can complete their review.
Physics F and G worked on correcting their Chapter 4 exams. On Monday, Physics F will review kinetic and potential energy and engage in a discussion of conservation and transformation of energy. Physics G will conduct a lab investigation centering around kinetic/elastic potential energy transformations in a mass-spring system and the conservation of that energy during oscillation.
Homework
Honors Physics: Complete lab write up. Complete yesterday’s homework assignment.
Physical Science B and F: Prepare for Chapter 11 exam
Physics F and G: Complete test corrections.
Physical Science B continued reviewing for the exam, but E Block was lost due to Peer Mentoring. Accordingly, we will have to delay the exam until Tuesday, so that E Block can complete their review.
Physics F and G worked on correcting their Chapter 4 exams. On Monday, Physics F will review kinetic and potential energy and engage in a discussion of conservation and transformation of energy. Physics G will conduct a lab investigation centering around kinetic/elastic potential energy transformations in a mass-spring system and the conservation of that energy during oscillation.
Homework
Honors Physics: Complete lab write up. Complete yesterday’s homework assignment.
Physical Science B and F: Prepare for Chapter 11 exam
Physics F and G: Complete test corrections.
10/22/09
Work and More Work
With everything going on I forgot to give Honors Physics A their lab sheets for tomorrow. No matter, the experiment is pretty straightforward. The lab deals with energy and how it can be converted from one form to the next. You remember from other science courses that energy is a conserved value. It can neither increase nor decrease in a closed system, it can only be converted from one form to another. You will be looking at the conversion of energy from potential (energy available to do work) to kinetic (energy involved with active work) and back again in a mass-spring system. You will monitor changes in the amount of potential, kinetic energies and total mechanical energy in the system as the spring moves in the vertical plane. Reading over the section on conservation of energy in your chapter will help you prepare for the lab if you don’t remember this concept well from physical science or chemistry classes. Today, we took a stroll through work and its connection to kinetic energy. Keep in mind to read problems carefully to determine exactly what is being asked and the configuration of the forces acting on the object. We’ll go over the homework questions on Monday and relate them to the results you obtained in lab.
Physical Science B conducted a lab investigation about momentum. If you increase either mass or velocity, you expect an increase in an object’s momentum. The more acceleration time you gave your cart, the greater its velocity and momentum. When it collided with the box, the cart with the greater momentum had more to transfer to the box and the box was set in motion with a greater initial velocity. Since all the boxes experienced the same acceleration due to friction, a higher initial velocity meant the box traveled longer (and farter) than when it was hit by a lower-velocity cart. Physical Science E continued their exam review by practicing problems with universal gravitation. We really didn’t get any farther than that and it was agreed that a further day of preparation was required before assessment. So, for both B and E Blocks, the exam has been rescheduled to Monday.
Physics F and G discussed kinetic and potential energy and the ability of one to be converted into the other. Though both are reported in Joules, remember that objects have to be moving to have kinetic energy. At rest, they possess one or more forms of potential energy. We also connected work and energy changes. If an object experiences a change in either kinetic or potential energy, work had to be involved. If an object gains energy, work was done on the object; if the object loses energy, it did work on another object. The lab for this chapter deals with the energy types and the ability to be converted. Physics G will conduct the lab on Monday and Physics F follows on Tuesday.
Homework
Honors Physics A: 5.1 Section Review, Practice 5C
Physical Science B: Complete lab write up. Prepare and practice for Monday’s exam
Physical Science E: Prepare and practice for Monday’s exam
Physics F and G: Practice 5C #4, 5D #1, 5.2 SR #1,2,3,5
Physical Science B conducted a lab investigation about momentum. If you increase either mass or velocity, you expect an increase in an object’s momentum. The more acceleration time you gave your cart, the greater its velocity and momentum. When it collided with the box, the cart with the greater momentum had more to transfer to the box and the box was set in motion with a greater initial velocity. Since all the boxes experienced the same acceleration due to friction, a higher initial velocity meant the box traveled longer (and farter) than when it was hit by a lower-velocity cart. Physical Science E continued their exam review by practicing problems with universal gravitation. We really didn’t get any farther than that and it was agreed that a further day of preparation was required before assessment. So, for both B and E Blocks, the exam has been rescheduled to Monday.
Physics F and G discussed kinetic and potential energy and the ability of one to be converted into the other. Though both are reported in Joules, remember that objects have to be moving to have kinetic energy. At rest, they possess one or more forms of potential energy. We also connected work and energy changes. If an object experiences a change in either kinetic or potential energy, work had to be involved. If an object gains energy, work was done on the object; if the object loses energy, it did work on another object. The lab for this chapter deals with the energy types and the ability to be converted. Physics G will conduct the lab on Monday and Physics F follows on Tuesday.
Homework
Honors Physics A: 5.1 Section Review, Practice 5C
Physical Science B: Complete lab write up. Prepare and practice for Monday’s exam
Physical Science E: Prepare and practice for Monday’s exam
Physics F and G: Practice 5C #4, 5D #1, 5.2 SR #1,2,3,5
10/21/09
Does Anyone Like Getting Up When Its Dark?
I think there should be a law that no one has to get up or go to work if it is still dark outside. I'm not sure how third-shifters would be able to stay employed, but I'm sure someone would think of something...
Honors Physics battled their forces and laws of motion exam today and some will continue the battle tomorrow morning. I haven’t even looked at the papers yet, so I can’t give you a head’s up on the performance rating, but people were definitely looking like they were giving it their best go. Tomorrow, we’ll start discussing work and kinetic energy. The lab on Friday will concentrate on the conservation of energy in simple harmonic motion, so the reading you’ll do tomorrow night should prep you for that investigation.
Physical Science B started their exam review and spent some time working review problems for universal gravitation. As promised, I found worksheets dealing with GRAVITY and MOMENTUM that you can work on for extra practice. Tomorrow, we’ll do the momentum lab without extensions so that we can have a little time at the end for more review. Physical Science E completed their discussion of conservation of momentum and began the review process for Friday’s exam. You can also access the extra GRAVITY and MOMENTUM worksheets and bring questions with you to class tomorrow. For both blocks, #6 of the momentum worksheet can be skipped. You have to use some of the kinematics formulas that we didn't go over in class, but you can give it a whirl with your MCAS formulas sheet, if you like!
Physics F and G began their exploration of work today and found that it is not exactly what they might have thought. Many people equate force and work; however, you can apply a gigantic force and still do not do work if the object doesn’t move. Plus, don’t forget that the force used to calculate work might only be a component of the total applied force. Vectors rear their ugly head again in that you can only use the component of force in the plane of the object’s motion to assess work. Tomorrow, we start in on kinetic energy and its relationship to work.
Homework
Honors Physics: None
Physical Science B: Read lab sheet and review for exam
Physical Science E: Review for exam
Physics F and G: Read pgs. 172-176 and complete Practice 5B #1, 2, 5
Honors Physics battled their forces and laws of motion exam today and some will continue the battle tomorrow morning. I haven’t even looked at the papers yet, so I can’t give you a head’s up on the performance rating, but people were definitely looking like they were giving it their best go. Tomorrow, we’ll start discussing work and kinetic energy. The lab on Friday will concentrate on the conservation of energy in simple harmonic motion, so the reading you’ll do tomorrow night should prep you for that investigation.
Physical Science B started their exam review and spent some time working review problems for universal gravitation. As promised, I found worksheets dealing with GRAVITY and MOMENTUM that you can work on for extra practice. Tomorrow, we’ll do the momentum lab without extensions so that we can have a little time at the end for more review. Physical Science E completed their discussion of conservation of momentum and began the review process for Friday’s exam. You can also access the extra GRAVITY and MOMENTUM worksheets and bring questions with you to class tomorrow. For both blocks, #6 of the momentum worksheet can be skipped. You have to use some of the kinematics formulas that we didn't go over in class, but you can give it a whirl with your MCAS formulas sheet, if you like!
Physics F and G began their exploration of work today and found that it is not exactly what they might have thought. Many people equate force and work; however, you can apply a gigantic force and still do not do work if the object doesn’t move. Plus, don’t forget that the force used to calculate work might only be a component of the total applied force. Vectors rear their ugly head again in that you can only use the component of force in the plane of the object’s motion to assess work. Tomorrow, we start in on kinetic energy and its relationship to work.
Homework
Honors Physics: None
Physical Science B: Read lab sheet and review for exam
Physical Science E: Review for exam
Physics F and G: Read pgs. 172-176 and complete Practice 5B #1, 2, 5
10/20/09
Exams and Exam Preparations
Honors Physics took an extra day to prepare for tomorrow’s assessment on forces and laws of motion. The good thing about this chapter is that it uses skills that you practiced in previous units. The bad thing about this chapter is that it uses skills that you practiced in previous units, only they don’t tell you that directly. You have to be ever-vigilant for vector operations and for situations involving kinematics. Also, this chapter truly challenges you to read and understand a problem and then plan an effective strategy towards its solution. This will pretty much be the rule for most chapters we cover this year and it is good to get used to the habits of mind early on. Exam tomorrow and starting Chapter 5 on Thursday.
Physics B discussed conservation of momentum and how it stems from the concepts of impulse and Newton’s 3rd Law of Motion. Always keep in mind that in a collision, the momentum lost by one object is gained by the other object in the interaction, conserving the system’s total momentum. We’ll do some review of this and other topics tomorrow and your lab on Thursday will allow you to work in more depth with the concept of momentum. We should also have some time after the lab for exam review. Physical Science E discussed their lab investigations and the momentum practice problems assigned Friday. Take time this evening to rework those that you got wrong and analyze what type of errors you are making. We’ll complete our discussion of momentum conservation tomorrow and use the rest of the period, as well as the whole period on Thursday to review for Friday’s exam.
Physics F and G suffered through their Chapter 4 exams. Tomorrow, we build upon our concept of force to understand work, power and energy - all words with common meanings that differ from the scientific meanings.
Homework
Honors Physics: Study for exam
Physical Science B and E: 11.3 Section Review
Physics F and G: Practice 5A and 5.1 Section Review #1-4
Physics B discussed conservation of momentum and how it stems from the concepts of impulse and Newton’s 3rd Law of Motion. Always keep in mind that in a collision, the momentum lost by one object is gained by the other object in the interaction, conserving the system’s total momentum. We’ll do some review of this and other topics tomorrow and your lab on Thursday will allow you to work in more depth with the concept of momentum. We should also have some time after the lab for exam review. Physical Science E discussed their lab investigations and the momentum practice problems assigned Friday. Take time this evening to rework those that you got wrong and analyze what type of errors you are making. We’ll complete our discussion of momentum conservation tomorrow and use the rest of the period, as well as the whole period on Thursday to review for Friday’s exam.
Physics F and G suffered through their Chapter 4 exams. Tomorrow, we build upon our concept of force to understand work, power and energy - all words with common meanings that differ from the scientific meanings.
Homework
Honors Physics: Study for exam
Physical Science B and E: 11.3 Section Review
Physics F and G: Practice 5A and 5.1 Section Review #1-4
10/19/09
Sunny Monday!
Well, I hope that everyone had a better weekend than me, as all I did was lie on the couch and berate the dogs for not taking of the household chores for me.
On Friday, Honors Physics worked on review problems for the Chapter 4 exam. After going over those problems today, it was pretty clear that an additional day of review is required before the test. So, go over your notes, problems sets and book and prepare questions to bring in tomorrow. We began reviewing the chapter in class today and got up to Newton’s 2nd and 3rd Laws of Motion. We’ll continue the chapter overview tomorrow and address any specific issues on content or problem-solving strategies. Exam is on Wednesday.
Physical Science ended last week by working a set of problems dealing with momentum. Always remember to keep an eye open for unit conversions required to work a problem – this set was rich with them and that is a pretty common situation. Physical Science B went over those problems today and E block will go over them tomorrow. Physical Science E engaged in an investigation of momentum, through the use of collisions. By varying the velocity of a constant mass, the momentum varied as a direct proportion. The more momentum, the harder it was to stop the moving cart; the less momentum, the easier it was to stop the moving cart. By adjusting the mass of the cart, a change was noticed in the interaction. Changing the mass of the cart would change the cart’s momentum, more mass - greater momentum, less mass - less momentum. We’ll discuss momentum and its conservation if more detail in class tomorrow.
Physics F and G watched a film about the speed of light on Friday and should be grateful for that fact. The number of films I show in that course can be counted on one hand with 4 fingers and a thumb left over. The film was a good one, though, to introduce the unusual (to our daily observations) phenomena associated with the speed of light and techniques that scientists are considering for trying to break that velocity barrier. Today, we briefly went over the discussion questions for the film and then completed the review for tomorrow’s exam. On Wednesday – work!
Homework
Honors Physics: Prepare review questions and complete friction lab (if necessary)
Physical Science B: Review momentum problems
Physical Science E: Complete lab write up
Physics F and G: Study for exam
On Friday, Honors Physics worked on review problems for the Chapter 4 exam. After going over those problems today, it was pretty clear that an additional day of review is required before the test. So, go over your notes, problems sets and book and prepare questions to bring in tomorrow. We began reviewing the chapter in class today and got up to Newton’s 2nd and 3rd Laws of Motion. We’ll continue the chapter overview tomorrow and address any specific issues on content or problem-solving strategies. Exam is on Wednesday.
Physical Science ended last week by working a set of problems dealing with momentum. Always remember to keep an eye open for unit conversions required to work a problem – this set was rich with them and that is a pretty common situation. Physical Science B went over those problems today and E block will go over them tomorrow. Physical Science E engaged in an investigation of momentum, through the use of collisions. By varying the velocity of a constant mass, the momentum varied as a direct proportion. The more momentum, the harder it was to stop the moving cart; the less momentum, the easier it was to stop the moving cart. By adjusting the mass of the cart, a change was noticed in the interaction. Changing the mass of the cart would change the cart’s momentum, more mass - greater momentum, less mass - less momentum. We’ll discuss momentum and its conservation if more detail in class tomorrow.
Physics F and G watched a film about the speed of light on Friday and should be grateful for that fact. The number of films I show in that course can be counted on one hand with 4 fingers and a thumb left over. The film was a good one, though, to introduce the unusual (to our daily observations) phenomena associated with the speed of light and techniques that scientists are considering for trying to break that velocity barrier. Today, we briefly went over the discussion questions for the film and then completed the review for tomorrow’s exam. On Wednesday – work!
Homework
Honors Physics: Prepare review questions and complete friction lab (if necessary)
Physical Science B: Review momentum problems
Physical Science E: Complete lab write up
Physics F and G: Study for exam
10/15/09
Teetering on the Brink
Back! Back you foul contagions! Pardon me while I whip out my arsenal and try to fight off the marauding hordes…
Ok...I'm back...but I am doubting my efforts will amount to much...
Honors Physics reviewed their lab and the homework problems assigned a few days ago. Those problems were quite robust in the number of skills required to affect a solution. You have to really draw on your knowledge of forces and motion to approach those problems and , actually, that is the way that real-life situations actually work. With the extra time needed for test preparation, the exam is postponed until at least Monday and we’ll use tomorrow for review. Try reworking problems that gave you difficulty today and see if our discussion helped you sort things out.
Physical Science B completed their discussion of Newton’s 3rd Law of Motion and used that to segue into an examination of momentum. If we were to follow Newton’s lines of thought, we would have examined momentum first, but doing it now is not a problem. Momentum actually helps people understand Newton’s laws a little better and adds a dimension of analysis for our study of motion. Physical Science E had this discussion yesterday and added more study of the concept of impulse today. Impulse is a pretty common-sense topic – an object’s change of momentum depends on the size of the applied force and the length of time that force is applied. We can also turn around our thinking to consider that the size of the force depends on how much momentum change was produced and how quickly it occurred. Both perspectives have many daily-life applications, and it is nice to be able to use one formula to attack a wide variety of problem types.
Physics F discussed air resistance and how it affects the motion of falling objects. For falling objects, terminal velocity can come into play if the object has sufficient time to fall, and air resistance offers the explanation for why heavier objects fall to the ground faster than lighter objects. Your lab tomorrow will allow you investigate air resistance for two objects that differ profoundly in mass.
Physics G conducted a lab centered around air resistance and found, unsurprisingly, that the velocity of a falling textbook was greater than the velocity of a falling coffee filter. Further, increasing numbers of stacked coffee filters fell with increasing velocity. A single coffee filter hit terminal velocity pretty quickly; the book didn’t have time to reach it at all. Five coffee filters took longer to hit terminal velocity than did fewer coffee filters. All those results would be predicted by our discussion of air resistance’s effects and you should be able to craft a nice discussion section for your lab synopsis based on this knowledge.
Homework
Honors Physics: Rework homework problems, if necessary.
Physical Science B and E: None
Physics F: Read lab sheet. Complete p. 153 #32-36 for Monday.
Physics G: Complete lab write up
Ok...I'm back...but I am doubting my efforts will amount to much...
Honors Physics reviewed their lab and the homework problems assigned a few days ago. Those problems were quite robust in the number of skills required to affect a solution. You have to really draw on your knowledge of forces and motion to approach those problems and , actually, that is the way that real-life situations actually work. With the extra time needed for test preparation, the exam is postponed until at least Monday and we’ll use tomorrow for review. Try reworking problems that gave you difficulty today and see if our discussion helped you sort things out.
Physical Science B completed their discussion of Newton’s 3rd Law of Motion and used that to segue into an examination of momentum. If we were to follow Newton’s lines of thought, we would have examined momentum first, but doing it now is not a problem. Momentum actually helps people understand Newton’s laws a little better and adds a dimension of analysis for our study of motion. Physical Science E had this discussion yesterday and added more study of the concept of impulse today. Impulse is a pretty common-sense topic – an object’s change of momentum depends on the size of the applied force and the length of time that force is applied. We can also turn around our thinking to consider that the size of the force depends on how much momentum change was produced and how quickly it occurred. Both perspectives have many daily-life applications, and it is nice to be able to use one formula to attack a wide variety of problem types.
Physics F discussed air resistance and how it affects the motion of falling objects. For falling objects, terminal velocity can come into play if the object has sufficient time to fall, and air resistance offers the explanation for why heavier objects fall to the ground faster than lighter objects. Your lab tomorrow will allow you investigate air resistance for two objects that differ profoundly in mass.
Physics G conducted a lab centered around air resistance and found, unsurprisingly, that the velocity of a falling textbook was greater than the velocity of a falling coffee filter. Further, increasing numbers of stacked coffee filters fell with increasing velocity. A single coffee filter hit terminal velocity pretty quickly; the book didn’t have time to reach it at all. Five coffee filters took longer to hit terminal velocity than did fewer coffee filters. All those results would be predicted by our discussion of air resistance’s effects and you should be able to craft a nice discussion section for your lab synopsis based on this knowledge.
Homework
Honors Physics: Rework homework problems, if necessary.
Physical Science B and E: None
Physics F: Read lab sheet. Complete p. 153 #32-36 for Monday.
Physics G: Complete lab write up
10/14/09
Brrrr.....
Mark your calendars – this was the first day this year I’ve had to scrape my windshield…
Honors Physics conducted an investigation into static and kinetic friction. Results were quite good – groups’ graphs for the motion of the objects looked as predicted and values for the coefficient of friction showed the predicted pattern as we changed the mass of the system. Tomorrow, we will discuss the lab, go over the homework problems and tidy up any loose ends before Friday’s exam.
Physical Science B reviewed their Newton’s 2nd Law of Motion Lab and built on yesterday’s work with orbital motion with a discussion and demonstration of projectile motion. Take home message – projectile motion is 2-dimensional motion and the x-(horizontal) and y-(vertical) components of the motion are independent of each other. The horizontal motion is at constant velocity (if we discount air resistance) due to the lack on an unbalanced force to accelerate the object. Motion in the vertical direction is accelerated by gravity, so the velocity in the y-direction increases with time. We also started looking at Newton’s 3rd Law of Motion and will continue on with that discussion tomorrow.
Physical Science E completed their examination of projectile motion with a demonstration of the independence of the horizontal and vertical motion vectors and launched into a discussion of Newton’s 3rd Law of Motion. Probably the most misunderstood of his laws of motion, Newton’s 3rd refers only to the magnitude and direction of the forces generated in an interaction between two objects, not to the responses of those objects to the forces. You have to back to Newton’s 2nd Law of Motion to determine the resulting acceleration of the objects. Our work with Newton 3 will lead us into another very important concept in physics – momentum and its conservation.
Physics F discussed the nature of static and kinetic friction and the use of the coefficient of friction in determine friction’s magnitude. Note that I changed the homework assignment by omitting #3 of the 4.4 section review. Physics G engaged in an examination of air resistance and terminal velocity. Tomorrow’s lab will concentrate on the impact of air resistance on the motion of objects – contrasting a low-inertia and high-inertia object as they fall. Both groups should be looking towards next Tuesday for their Chapter 4 exam.
Homework
Honors Physics: Complete lab write up (for Monday) and homework problems
Physical Science B an E: None
Physics F: Practice 4D #2 and 4.4 Section Review #2, 4-6
Physics G: Read lab sheet. Complete p. 153 #32-36 for Friday
Honors Physics conducted an investigation into static and kinetic friction. Results were quite good – groups’ graphs for the motion of the objects looked as predicted and values for the coefficient of friction showed the predicted pattern as we changed the mass of the system. Tomorrow, we will discuss the lab, go over the homework problems and tidy up any loose ends before Friday’s exam.
Physical Science B reviewed their Newton’s 2nd Law of Motion Lab and built on yesterday’s work with orbital motion with a discussion and demonstration of projectile motion. Take home message – projectile motion is 2-dimensional motion and the x-(horizontal) and y-(vertical) components of the motion are independent of each other. The horizontal motion is at constant velocity (if we discount air resistance) due to the lack on an unbalanced force to accelerate the object. Motion in the vertical direction is accelerated by gravity, so the velocity in the y-direction increases with time. We also started looking at Newton’s 3rd Law of Motion and will continue on with that discussion tomorrow.
Physical Science E completed their examination of projectile motion with a demonstration of the independence of the horizontal and vertical motion vectors and launched into a discussion of Newton’s 3rd Law of Motion. Probably the most misunderstood of his laws of motion, Newton’s 3rd refers only to the magnitude and direction of the forces generated in an interaction between two objects, not to the responses of those objects to the forces. You have to back to Newton’s 2nd Law of Motion to determine the resulting acceleration of the objects. Our work with Newton 3 will lead us into another very important concept in physics – momentum and its conservation.
Physics F discussed the nature of static and kinetic friction and the use of the coefficient of friction in determine friction’s magnitude. Note that I changed the homework assignment by omitting #3 of the 4.4 section review. Physics G engaged in an examination of air resistance and terminal velocity. Tomorrow’s lab will concentrate on the impact of air resistance on the motion of objects – contrasting a low-inertia and high-inertia object as they fall. Both groups should be looking towards next Tuesday for their Chapter 4 exam.
Homework
Honors Physics: Complete lab write up (for Monday) and homework problems
Physical Science B an E: None
Physics F: Practice 4D #2 and 4.4 Section Review #2, 4-6
Physics G: Read lab sheet. Complete p. 153 #32-36 for Friday
10/13/09
Goodbye, Columbus
A dreary Tuesday after a long weekend – not the most auspicious way to start the week, but we seemed to manage fine…
Honors Physics completed their discussion of friction with an examination of the impact of air resistance on motion. Tomorrow’s lab targets friction, both static and kinetic, and the problems due Thursday will give you a good bit of practice with the quantitative aspect of friction studies.
Physical Science B investigated Newton’s 2nd Law of Motion with an activity that used a constant force to accelerate various masses. As predicted, the larger the mass (inertia), the less the acceleration. Hopefully, for the extension, you realized that with the same mass sets, an increased force would produce an increased acceleration. We will discuss the lab tomorrow and continue on with our examination of projectile motion.
Physical Science E discussed free fall and its relationship to “weightlessness.” Motion in something like the space shuttle is actually only apparently weightless due to the fact that both the shuttle and the astronauts exist in constant free fall. Our discussion then turned towards orbital motion and projectile motion. We will continue on with this tomorrow and include a demonstration of the independence of horizontal and velocity vectors in projectile motion.
Physics F discussed weight and the normal force today, for objects on horizontal surfaces and on inclines. These concepts will lead us into a discussion of frictional forces, which depend on the magnitude of the normal force to which an object is exposed. Physics G continued their discussion of friction and the coefficient of friction. Static friction trumps kinetic friction in magnitude, so it is not surprising that the coefficient of static friction is larger than the corresponding coefficient of kinetic friction for the same two surfaces in contact. In problems, you could be asked to solve for the friction in a system or for the coefficient of friction. First, you will need to calculate the normal force on the object if it is provided, and then complete the problem with that information. Also, pay attention for situations where an object is slowing down. If friction is the only force acting on the object (in the horizontal direction), then you can use the acceleration to calculate the frictional force (m x a).
Homework
Honors Physics: Read lab sheet for tomorrow and complete 4D and ChRev #39, 53, 68 for Thursday
Physical Science B: None
Physical Science E: Complete lab write up
Physics F: p. 153 26-30. Do only items a and c for question 28 and answer question 29 only for items a and c of question 28.
Physics G: 4C #2, 4.4 Section Review #2-6
Honors Physics completed their discussion of friction with an examination of the impact of air resistance on motion. Tomorrow’s lab targets friction, both static and kinetic, and the problems due Thursday will give you a good bit of practice with the quantitative aspect of friction studies.
Physical Science B investigated Newton’s 2nd Law of Motion with an activity that used a constant force to accelerate various masses. As predicted, the larger the mass (inertia), the less the acceleration. Hopefully, for the extension, you realized that with the same mass sets, an increased force would produce an increased acceleration. We will discuss the lab tomorrow and continue on with our examination of projectile motion.
Physical Science E discussed free fall and its relationship to “weightlessness.” Motion in something like the space shuttle is actually only apparently weightless due to the fact that both the shuttle and the astronauts exist in constant free fall. Our discussion then turned towards orbital motion and projectile motion. We will continue on with this tomorrow and include a demonstration of the independence of horizontal and velocity vectors in projectile motion.
Physics F discussed weight and the normal force today, for objects on horizontal surfaces and on inclines. These concepts will lead us into a discussion of frictional forces, which depend on the magnitude of the normal force to which an object is exposed. Physics G continued their discussion of friction and the coefficient of friction. Static friction trumps kinetic friction in magnitude, so it is not surprising that the coefficient of static friction is larger than the corresponding coefficient of kinetic friction for the same two surfaces in contact. In problems, you could be asked to solve for the friction in a system or for the coefficient of friction. First, you will need to calculate the normal force on the object if it is provided, and then complete the problem with that information. Also, pay attention for situations where an object is slowing down. If friction is the only force acting on the object (in the horizontal direction), then you can use the acceleration to calculate the frictional force (m x a).
Homework
Honors Physics: Read lab sheet for tomorrow and complete 4D and ChRev #39, 53, 68 for Thursday
Physical Science B: None
Physical Science E: Complete lab write up
Physics F: p. 153 26-30. Do only items a and c for question 28 and answer question 29 only for items a and c of question 28.
Physics G: 4C #2, 4.4 Section Review #2-6
10/11/09
Reading
Since one of you rapscallions infected me again with some cold/flu bug, I am confined to the house, having to entertain myself. Of course, I do have my Xbox 360, HDTV with Netflix and Amazon Video on Demand and craft supplies sufficient to stock an AC Moore, but what I've been doing is reading. Terry Pratchett has a new book out
and I grabbed it for my Kindle yesterday morning. Finishing that one, I went back into my library and began rereading (many for the nth time) some of of his older titles. Great comic fantasy with strong characters and interesting plots. Here are some of my favorites:
With Moist von Lipwig:
With Sam Vimes and the Night Watch:
With Granny Weatherwax:
With Death:
and I grabbed it for my Kindle yesterday morning. Finishing that one, I went back into my library and began rereading (many for the nth time) some of of his older titles. Great comic fantasy with strong characters and interesting plots. Here are some of my favorites:
With Moist von Lipwig:
With Sam Vimes and the Night Watch:
With Granny Weatherwax:
With Death:
10/8/09
Winding Down the Week
Honors Physics reviewed the process of using Newton’s 2nd Law of Motion to solve for an object’s acceleration. Remember that an acceleration given in a problem is a product of the net force and before you can calculate acceleration, you must first find the net force acting on the object. This is where free-body diagrams come in handy – they give you a way to visualize a problem and determine where forces are acting. With an incline, remember to break down an object’s weight into components and watch for objects being pushed or pulled at an angle while on an incline. Today, we discussed the nature of frictional resistance and the basic meaning of coefficients of friction. You should be use coefficients of friction to calculate the static or kinetic friction acting on an object and the object’s resultant acceleration.
Physical Science B further discussed gravity and its connection to weight. Towards the end of the period, we took time to discuss and demonstrate “apparent weightlessness” and explore the concept of orbital motion. On Tuesday, you will conduct a lab to examine Newton’s 2nd Law of Motion in more detail before we start projectile motion on Wednesday.
Physical Science E took the class period to review their universal gravitation problems. Folks are having difficulties with calculators, especially with the use of scientific notation. To determine how best to work with scientific notation on your calculator, give yourself a simple problem (one for which you know the answer) and work it until you find the correct keystroke order to work the problem. The worksheet answers are still online – the link can be found 2 posts ago – see if you can remedy your difficulties somewhat over the weekend and we will address the problems again when you return on Tuesday.
Physics F discussed Newton’s 2nd and 3rd Laws of Motion. Remember that when we discuss Newton’s laws of motion, they exist irrespective of the force involved in the problem. The action of both field and contact forces are described by the laws of motion, so they will apply to any problems that you are asked to solve. Physics G explored the concepts of weight and the normal force and began a discussion of the nature of friction. Think back to your lab investigation as we move through friction and consider how your observations during the experiment are explained by the theory.
Homework
Physics A: 4D and Chapter Review # 39, 53 and 68 for Wednesday
Physics B: None
Physics E: Reexamine your gravity problems and look for sources of error. Practice your calculator skills
Physics F: None
Physics G: p. 153 26-30. Do only items a and c for question 28 and answer question 29 only for items a and c of question 28.
HAVE A GREAT LONG WEEKEND!
Physical Science B further discussed gravity and its connection to weight. Towards the end of the period, we took time to discuss and demonstrate “apparent weightlessness” and explore the concept of orbital motion. On Tuesday, you will conduct a lab to examine Newton’s 2nd Law of Motion in more detail before we start projectile motion on Wednesday.
Physical Science E took the class period to review their universal gravitation problems. Folks are having difficulties with calculators, especially with the use of scientific notation. To determine how best to work with scientific notation on your calculator, give yourself a simple problem (one for which you know the answer) and work it until you find the correct keystroke order to work the problem. The worksheet answers are still online – the link can be found 2 posts ago – see if you can remedy your difficulties somewhat over the weekend and we will address the problems again when you return on Tuesday.
Physics F discussed Newton’s 2nd and 3rd Laws of Motion. Remember that when we discuss Newton’s laws of motion, they exist irrespective of the force involved in the problem. The action of both field and contact forces are described by the laws of motion, so they will apply to any problems that you are asked to solve. Physics G explored the concepts of weight and the normal force and began a discussion of the nature of friction. Think back to your lab investigation as we move through friction and consider how your observations during the experiment are explained by the theory.
Homework
Physics A: 4D and Chapter Review # 39, 53 and 68 for Wednesday
Physics B: None
Physics E: Reexamine your gravity problems and look for sources of error. Practice your calculator skills
Physics F: None
Physics G: p. 153 26-30. Do only items a and c for question 28 and answer question 29 only for items a and c of question 28.
HAVE A GREAT LONG WEEKEND!
10/7/09
A Day o' Math
Honors Physics rode through weight and the normal force in fine fashion today and then began to wrestle with friction. We discussed both static and kinetic friction and will take time tomorrow to more fully contrast the two and examine methods for calculating frictional forces. The ability to resolve an object’s weight will be very helpful for problems that involve motion on an incline. Adding weight, normal force and friction to the pot will make analyzing motion of objects a bit more complex. Take care drawing your free-body diagrams to isolate all forces in play and consider how those forces will be calculated. Acceleration is only produced by the net external force, so if you leave a force out of the picture, you will incorrectly describe the object’s motion.
Physical Science B rioted for awhile when they realized that math is going to plague them throughout the year and that they had best get used to working with equations and their calculators. Today, we reviewed the universal gravitation formula and the problems that we assigned last night. From what I can tell, calculator use is a major issue, as is working with a multivariable equation. You will get lots of practice with both this year, so a rocky start doesn’t mean that you are doomed completely. Take time tonight to rework the homework problems and ask yourself if your difficulties lie in setting up the problem, your solution method or problems with your calculator. If you need extra help or additional problems to work, feel free to ask. Tomorrow, we continue on with gravity and the acceleration that it produces on objects.
Physical Science E discussed yesterday’s lab, which nicely demonstrated the relationship between force, mass (inertia) and acceleration predicted by Newton’s 2nd Law of Motion. We went over our homework problems from Monday and began a discussion about gravity. They also received the dreaded universal gravitation problems packet. Check the previous post for the link to the solutions key for that problem set. We will go over them tomorrow, but do your very best to work through each problem as far as you can. As for all math problems, try and figure out where your main difficulty lies and ask for extra help on that piece.
Physics F discussed their lab investigation and discussed the nature of forces and the use of force and free-body diagrams to analyze forces acting on an object. Tomorrow, we will learn how to calculate the net force acting on an object and the acceleration produced by that force. Physics G had that discussion today, along with an examination of Newton’s 3rd Law of Motion. From the Vernier demo, it was pretty clear that forces generated in an interaction are equal in magnitude but opposite in direction. That pattern holds whether the interaction is between two Sumo wrestlers, a mosquito and a car or a baseball and baseball bat. Remember that the idea of equal and opposite, though, applies to the forces involved, not the responses of the objects.
Homework
Honors Physics: None
Physical Science B: Rework gravity problems, as necessary
Physical Science E: Gravity problems worksheet
Physics F: 4.2 Section Review and #1-5 on page 151
Physics G: p. 152 #13-18, #20
Physical Science B rioted for awhile when they realized that math is going to plague them throughout the year and that they had best get used to working with equations and their calculators. Today, we reviewed the universal gravitation formula and the problems that we assigned last night. From what I can tell, calculator use is a major issue, as is working with a multivariable equation. You will get lots of practice with both this year, so a rocky start doesn’t mean that you are doomed completely. Take time tonight to rework the homework problems and ask yourself if your difficulties lie in setting up the problem, your solution method or problems with your calculator. If you need extra help or additional problems to work, feel free to ask. Tomorrow, we continue on with gravity and the acceleration that it produces on objects.
Physical Science E discussed yesterday’s lab, which nicely demonstrated the relationship between force, mass (inertia) and acceleration predicted by Newton’s 2nd Law of Motion. We went over our homework problems from Monday and began a discussion about gravity. They also received the dreaded universal gravitation problems packet. Check the previous post for the link to the solutions key for that problem set. We will go over them tomorrow, but do your very best to work through each problem as far as you can. As for all math problems, try and figure out where your main difficulty lies and ask for extra help on that piece.
Physics F discussed their lab investigation and discussed the nature of forces and the use of force and free-body diagrams to analyze forces acting on an object. Tomorrow, we will learn how to calculate the net force acting on an object and the acceleration produced by that force. Physics G had that discussion today, along with an examination of Newton’s 3rd Law of Motion. From the Vernier demo, it was pretty clear that forces generated in an interaction are equal in magnitude but opposite in direction. That pattern holds whether the interaction is between two Sumo wrestlers, a mosquito and a car or a baseball and baseball bat. Remember that the idea of equal and opposite, though, applies to the forces involved, not the responses of the objects.
Homework
Honors Physics: None
Physical Science B: Rework gravity problems, as necessary
Physical Science E: Gravity problems worksheet
Physics F: 4.2 Section Review and #1-5 on page 151
Physics G: p. 152 #13-18, #20
10/6/09
Flyin' Carts!
Fall finally seems to be creeping in – it was almost chilly this morning! A word of note: the classroom can get quite cold in winter, so have something you can slip on in class stashed in your backpack.
Honors Physics discussed Newton’s 2nd and 3rd Laws of Motion and some of the misconceptions associated with these laws. For example, Newton’s 2nd Law is not simply a formula – it is a relationship between forces and an object’s inertia. Newton’s 3rd Law always gets mangled – action and reaction refer to the forces involved, not the responses of the objects. Response (acceleration) is dependent on the individual objects’ inertia. Also, the phrase “action-reaction pairs” implies a time lag that does not actually exist. When objects contact, the forces are generated instantaneously and simultaneously. Lastly, remember that these forces do not result in equilibrium – they act on different objects, not on a single object. Tomorrow, we will discuss weight and the normal force and should have time to make an inroad into friction. For the homework, you can omit #24 and 25. For some reason, the book expects you to know how to work with weight and its components before actually showing you how!
Physical Science B reviewed their Newton’s 2nd Law of Motion problems and began a discussion of gravity. The gravitational force between any two objects can be calculated using the formula: Fg = (Gm1m2)/r2. The problems set you have for homework tonight uses this formula to solve for force, mass or distance between objects. Talking to a couple of folks today, I think we might need a little review on the most efficient way to use exponents on your calculators. When working with scientific notation, using the caret key is not the best way for many brands of calculators. It is too easy to make a mistake. On the TI series that many of you have, type in the number, then hit the 2nd key, then the “,” key with has an EE on top. Then, type in your exponent, using + or -, as appropriate. The caret key is the key to use when typing an exponent for a number, something like 58. Click Here for the answer key for your worksheet problems.
Physical Science E worked on a lab that allowed students to assess the effect of mass (inertia) and force on the acceleration of an object. First, a variable mass was subjected to a constant force and, then, a variable force acted on a constant mass. From yesterday’s discussion of Newton’s 2nd Law of Motion, the results should make sense. Acceleration was directly proportional to applied force when mass is constant (greater force, greater acceleration) and inversely proportional to mass (inertia) when force is constant (greater inertia, less acceleration). Only a few carts went flying off of the lab tables, so I consider that a success. We will discuss this lab tomorrow and review the Chapter Review problems for Newton’s 2nd Law of Motion. Then, we jump into gravity!
Physics F completed their lab investigation on static and kinetic friction. Physics G began their discussion of forces with an overview of the concept of force and the use of free-body diagrams to assess net force. Remember to account for all forces with your diagram and draw them according to the standard guidelines - tail of force vector at center of object, tip of force vector pointing in direction of force.
Homework
Honors Physics: 4B and Chapter Review #21-23 (you can remove 25 and 25 from the assignment)
Physical Science B: Gravitational Forces worksheet
Physical Science E: Complete lab write up
Physics F: Work on lab write up
Physics G: Read 4.2 and complete 4.2 section review and p. 151 #1-5
Honors Physics discussed Newton’s 2nd and 3rd Laws of Motion and some of the misconceptions associated with these laws. For example, Newton’s 2nd Law is not simply a formula – it is a relationship between forces and an object’s inertia. Newton’s 3rd Law always gets mangled – action and reaction refer to the forces involved, not the responses of the objects. Response (acceleration) is dependent on the individual objects’ inertia. Also, the phrase “action-reaction pairs” implies a time lag that does not actually exist. When objects contact, the forces are generated instantaneously and simultaneously. Lastly, remember that these forces do not result in equilibrium – they act on different objects, not on a single object. Tomorrow, we will discuss weight and the normal force and should have time to make an inroad into friction. For the homework, you can omit #24 and 25. For some reason, the book expects you to know how to work with weight and its components before actually showing you how!
Physical Science B reviewed their Newton’s 2nd Law of Motion problems and began a discussion of gravity. The gravitational force between any two objects can be calculated using the formula: Fg = (Gm1m2)/r2. The problems set you have for homework tonight uses this formula to solve for force, mass or distance between objects. Talking to a couple of folks today, I think we might need a little review on the most efficient way to use exponents on your calculators. When working with scientific notation, using the caret key is not the best way for many brands of calculators. It is too easy to make a mistake. On the TI series that many of you have, type in the number, then hit the 2nd key, then the “,” key with has an EE on top. Then, type in your exponent, using + or -, as appropriate. The caret key is the key to use when typing an exponent for a number, something like 58. Click Here for the answer key for your worksheet problems.
Physical Science E worked on a lab that allowed students to assess the effect of mass (inertia) and force on the acceleration of an object. First, a variable mass was subjected to a constant force and, then, a variable force acted on a constant mass. From yesterday’s discussion of Newton’s 2nd Law of Motion, the results should make sense. Acceleration was directly proportional to applied force when mass is constant (greater force, greater acceleration) and inversely proportional to mass (inertia) when force is constant (greater inertia, less acceleration). Only a few carts went flying off of the lab tables, so I consider that a success. We will discuss this lab tomorrow and review the Chapter Review problems for Newton’s 2nd Law of Motion. Then, we jump into gravity!
Physics F completed their lab investigation on static and kinetic friction. Physics G began their discussion of forces with an overview of the concept of force and the use of free-body diagrams to assess net force. Remember to account for all forces with your diagram and draw them according to the standard guidelines - tail of force vector at center of object, tip of force vector pointing in direction of force.
Homework
Honors Physics: 4B and Chapter Review #21-23 (you can remove 25 and 25 from the assignment)
Physical Science B: Gravitational Forces worksheet
Physical Science E: Complete lab write up
Physics F: Work on lab write up
Physics G: Read 4.2 and complete 4.2 section review and p. 151 #1-5
10/5/09
The Force is Physics
Forces are on the docket today for all classes. Physics F and G are working on labs focused on static/kinetic friction and action-reaction pairs. Honors Physics discussed the nature of forces, construction of free-body diagrams and calculation of net forces. Physical Science dug into forces and how they interact with an object’s inertia to determine acceleration. Good start for a Monday!
Homework
Honors Physics: work on lab write up
Physical Science B: p.369 #22 – 27
Physical Science E: p. 369 #22 – 27 and read tomorrow’s lab activity
Physics F: None
Physics G: Work on lab write up and test corrections
Homework
Honors Physics: work on lab write up
Physical Science B: p.369 #22 – 27
Physical Science E: p. 369 #22 – 27 and read tomorrow’s lab activity
Physics F: None
Physics G: Work on lab write up and test corrections
10/2/09
Labs Ahoy!
Between running two labs and having to listen to freshmen class officer speeches, I am very ready for the weekend…
Honors Physics completed their Atwood’s Machine lab and got their Chapter 3 exams returned. Like I said in class, if your score was abysmal, you are in good company. This test always seems to hit students hard, and that is why I am allowing you to correct your tests for one-half the points you missed returned to your score. You must show all work and /or offer an explanation for why the correct answer is actually the correct one if you want to receive your credit. You can work together and use any resources that are available. Email me with any questions , also, but have those corrected papers back to me by the end of the day Monday. Don’t worry about your lab write-up right now, I won’t look at collecting that until Tuesday at the earliest.
Physical Science B had an abbreviated period due to the class officer speeches, but we had time to go over yesterday’s exam and for students to complete gathering the information for their labs. Have those ready to go for Monday, when we begin our study of forces. Physical Science E also went over their exams and took time preview the forces material that we will begin next week.
Physics F received their exam papers and worked on test corrections. Physics G embarked on two lab investigations that centered on forces. The first lab explored static and kinetic friction and the second targeted Newton’s 3rd law of Motion. We will cover these topics in depth starting next week when we begin Chapter 4. We will complete the lab on Monday and groups should have time to start on the data analysis in class. From what I saw of the friction data, people did a good job. It was clear that static friction was greater than kinetic friction and that objects moved with constant acceleration/velocity, as appropriate.
Homework
Honors Physics: Correct Chapter 3 exams (optional)
Physical Science B: Complete lab write up
Physical Science E: None
Physics F: Complete test corrections
Physics G: None
Honors Physics completed their Atwood’s Machine lab and got their Chapter 3 exams returned. Like I said in class, if your score was abysmal, you are in good company. This test always seems to hit students hard, and that is why I am allowing you to correct your tests for one-half the points you missed returned to your score. You must show all work and /or offer an explanation for why the correct answer is actually the correct one if you want to receive your credit. You can work together and use any resources that are available. Email me with any questions , also, but have those corrected papers back to me by the end of the day Monday. Don’t worry about your lab write-up right now, I won’t look at collecting that until Tuesday at the earliest.
Physical Science B had an abbreviated period due to the class officer speeches, but we had time to go over yesterday’s exam and for students to complete gathering the information for their labs. Have those ready to go for Monday, when we begin our study of forces. Physical Science E also went over their exams and took time preview the forces material that we will begin next week.
Physics F received their exam papers and worked on test corrections. Physics G embarked on two lab investigations that centered on forces. The first lab explored static and kinetic friction and the second targeted Newton’s 3rd law of Motion. We will cover these topics in depth starting next week when we begin Chapter 4. We will complete the lab on Monday and groups should have time to start on the data analysis in class. From what I saw of the friction data, people did a good job. It was clear that static friction was greater than kinetic friction and that objects moved with constant acceleration/velocity, as appropriate.
Homework
Honors Physics: Correct Chapter 3 exams (optional)
Physical Science B: Complete lab write up
Physical Science E: None
Physics F: Complete test corrections
Physics G: None
10/1/09
October - Day 1
4 of my 5 classes suffered through graded learning experiences. Physics and Physical Science contended with their assessments and will start new chapters tomorrow. Physical Science B needs to remember to bring their lab work with them so that we can complete the data analysis and discussion before you begin your write up. Physics G needs to remember to read their lab sheets in preparation of tomorrow’s work. Physical Science E and Physics F need to remember to take it easy and spare a little time for the homework that’s due tomorrow.
Honors Physics engaged in two lab activities. The Newton’s 2nd Law of Motion lab is a nice one for seeing the quantitative relationship between force, acceleration and mass for an object. We used the Vernier Dynamics Tracks purchased for the school by the Georgetown Education Foundation. These tracks provide a very low friction environment, so students get very clear and meaningful data. As we would predict, the graphs of force and acceleration were mirror images of each: force is directly proportional to acceleration if mass remains constant. The graph of force versus acceleration produced a nice linear relationship for which the slope was the object’s mass in kilograms. The second experiment, Atwood’s Machine is ongoing and will be completed in class tomorrow. Here are a couple of pics from today’s lab:
Homework:
Honors Physics: None
Physical Science B and E: Complete the 11.1 Section Review (even the Math Skills questions) and the Practice on page 351
Physics F: Read 4.1 in the book and complete the 4.1 Section Review
Physics G: Read the lab protocol sheet and complete the 4.1 Section Review by Monday
Honors Physics engaged in two lab activities. The Newton’s 2nd Law of Motion lab is a nice one for seeing the quantitative relationship between force, acceleration and mass for an object. We used the Vernier Dynamics Tracks purchased for the school by the Georgetown Education Foundation. These tracks provide a very low friction environment, so students get very clear and meaningful data. As we would predict, the graphs of force and acceleration were mirror images of each: force is directly proportional to acceleration if mass remains constant. The graph of force versus acceleration produced a nice linear relationship for which the slope was the object’s mass in kilograms. The second experiment, Atwood’s Machine is ongoing and will be completed in class tomorrow. Here are a couple of pics from today’s lab:
Homework:
Honors Physics: None
Physical Science B and E: Complete the 11.1 Section Review (even the Math Skills questions) and the Practice on page 351
Physics F: Read 4.1 in the book and complete the 4.1 Section Review
Physics G: Read the lab protocol sheet and complete the 4.1 Section Review by Monday
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