An ark - get one...
Honors Physics reviewed basic ideas about refraction and Snell’s Law before moving to mirrors. Converging and diverging lenses were discussed and patterns of image formation for each type of mirror was diagrammed. Tomorrow’s lab will allow students practice working with both types of lenses and both the thin lens equation and the magnification formula.
Physical Science B had a very hard time in lab today, since it is a tremendously wet day and the lab focused on static electricity. On wet days, there is an abundance of water molecules in the air that work to neutralize charges that objects acquire. That is why static cling is worst on dry days. But, the basic ideas were visible – objects can acquire a charge through friction, conduction or induction and that the resulting forces can produce a change in the motion of objects. There was time in class, also, to review over the Coulomb’s Law problems that were assigned for homework.
Physical Science E completed their discussion of electric field lines and field-line diagrams and then spent time working problems for Coulomb’s Law. The solutions are presented in Friday’s post, so check your work to see how you did before coming to class tomorrow. We’ll review these problems tomorrow and then turn attention towards electric current.
Physics F and G completed their discussion of light polarization and then started in on the refraction chapter. Refraction will occur when light crosses from one medium to a different medium. The properties of the second medium determine light’s new speed and path of travel. Using Snell’s Law, that new direction can be predicted and time was taken in class to practice working problems with Snell’s Law. Tomorrow – finishing up refraction for G Block and on to lenses for F Block.
Homework
Honors Physics A: Read lab protocol sheet for tomorrow and complete Practice 15B for Wednesday
Physical Science B: Complete lab write up and rework Coulomb’s Law problems, if necessary
Physical Science E: Complete Coulomb’s Law worksheet
Physics F: Conceptual Challenge p. 565, Practice 15A and 15.1 Section Review
Physics G: Ch14 Chapter Review #40,44; read 15.1 and complete the 15.1 Section Review
3/15/10
3/12/10
Funkie Friday
Honors Physics reviewed their work on color and polarization and then moved into the area of refraction. The relationship between EM wave speed and density of medium was reinforced and used to explain the index of refraction. Snell’s Law uses this relative speed of light in various media to predict what would be the angle of a refracted ray, give the angle of the incident ray and identities of the two media. The fact that refraction is wavelength dependent helped explain the concept of dispersion and different materials were compared on how the various wavelengths of visible light were slowed down as they passed through. The homework tonight will allow you to ponder the consequences of refraction and practice solving problems using Snell’s Law. On Monday, we’ll start looking at lenses and Tuesday’s lab activity will concentrate on image formation by converging and diverging lenses.
Physical Science B went over their sound and light exam and then began to work problems using Coulomb’s Law. For those problems, remember to convert any charge value presented with a metric prefix to its full value in scientific notation before placing them in the formula. Also, some problems might not seem to give you full information (especially about charge), but a little thinking about the situation should allow you to see past that to the solution. For your worksheet, here are the answers so you can check your work:
Note: if you use 9 x 109 N x m2/C2 as your value for “k,” your answers may be slightly different than those above. Monday, you’ll get to work on a lab that will let you see the effects of static charge and the forces that result. Then, it will be on to electric current.
Physical Science E discussed their sound and light exams and then continued their discussion of static charge and the forces produced. Coulomb's Law was discussed, as was the concept of electric field lines. Students learned how to interpret field line diagrams and use them to predict electric field strength. On Monday, we will go over the review questions for this section and then take time to practice using Coulomb's Law to solve electric force problems.
Physics F spent time going over review work for light, reflection and mirrors and then turned attention to color and polarization. You should be able to recognize the primary colors of the additive and subtractive color systems and predict which colors would result as you mix pigments or light or shine light on a pigmented substance.
Physics G tied up loose ends for light, reflection and mirrors. We spent time reviewing the mathematics of mirrors and will begin our discussion of color and polarization on Monday.
Homework
Honors Physics A: Complete Conceptual Challenge p. 565, 15.1 Section Review and Practiced 15A
Physical Science B and E: Complete Coulomb’s Law worksheet
Physics F: Complete Conceptual Challenge p. 545 and Chapter Review items #37-44
Physics G: Complete Conceptual Challenge p. 545
Physical Science B went over their sound and light exam and then began to work problems using Coulomb’s Law. For those problems, remember to convert any charge value presented with a metric prefix to its full value in scientific notation before placing them in the formula. Also, some problems might not seem to give you full information (especially about charge), but a little thinking about the situation should allow you to see past that to the solution. For your worksheet, here are the answers so you can check your work:
- 0.387 m
- 0.585 m
- 1.15 m
- -143 N
- 3.50 x 10-4 N
- 1.4 x 10-3 N
- 1.6 x 10-19 C
- 1.6 x 10-19 C
- 1.6 x 10-19 C
- 2.2 x 10-17 C
Note: if you use 9 x 109 N x m2/C2 as your value for “k,” your answers may be slightly different than those above. Monday, you’ll get to work on a lab that will let you see the effects of static charge and the forces that result. Then, it will be on to electric current.
Physical Science E discussed their sound and light exams and then continued their discussion of static charge and the forces produced. Coulomb's Law was discussed, as was the concept of electric field lines. Students learned how to interpret field line diagrams and use them to predict electric field strength. On Monday, we will go over the review questions for this section and then take time to practice using Coulomb's Law to solve electric force problems.
Physics F spent time going over review work for light, reflection and mirrors and then turned attention to color and polarization. You should be able to recognize the primary colors of the additive and subtractive color systems and predict which colors would result as you mix pigments or light or shine light on a pigmented substance.
Physics G tied up loose ends for light, reflection and mirrors. We spent time reviewing the mathematics of mirrors and will begin our discussion of color and polarization on Monday.
Homework
Honors Physics A: Complete Conceptual Challenge p. 565, 15.1 Section Review and Practiced 15A
Physical Science B and E: Complete Coulomb’s Law worksheet
Physics F: Complete Conceptual Challenge p. 545 and Chapter Review items #37-44
Physics G: Complete Conceptual Challenge p. 545
3/11/10
Mirrors, Fields and Forces
Honors Physics spent time discussing color and polarization. The additive and subtractive color systems can be tricky to work with, so spend time really thinking about your answers to the homework questions. Polarization is relatively straightforward and today’s videos showed just how dramatic the effects of polarization can be. Tomorrow, we’ll review these concepts and then move on to the next chapter – refraction.
Physical Science B discussed electric charge, fields and forces. The final two methods for producing a an electric charge on a neutral object (conduction and induction) and discussed examples of each. Folks got a chance to visualize electric fields with field line diagrams and describe changes in electric potential energy based on position change of a charged particle in an electric field. Finally, the formula for Coulomb’s Law was presented and compared with that for gravitational force. Both forces are directly dependent on the magnitude of the property of matter generating the force (mass for gravity and charge for electric force) and inversely proportional to distance squared. You’ll get math practice tomorrow with Coulomb’s Law so don’t forget your calculator.
Physical Science E reviewed their static electricity experiments and began to explore the concept of static charge in more detail. The property of charge was described and related to the production of electric forces and fields. Methods of charging neutral objects was discussed and the basic properties of the three main subatomic particles (protons, neutrons and electrons) were reviewed. Tomorrow, we’ll take a more quantitative look at electric forces and fields before moving on to electric current.
Physics F and G had a final discussion of their lab activities and then turned attention back to the properties of mirrors. Plane mirrors were reviewed and the characteristics of convex and concave mirrors were introduced. The rules for drawing ray diagrams were presented and students got some practice seeing how these diagrams verified the mirror equation.
Homework
Honors Physics A: Conceptual Challenge p. 545 and Chapter Review items #37-45
Physical Science B and E: None
Physics F and G: None
Physical Science B discussed electric charge, fields and forces. The final two methods for producing a an electric charge on a neutral object (conduction and induction) and discussed examples of each. Folks got a chance to visualize electric fields with field line diagrams and describe changes in electric potential energy based on position change of a charged particle in an electric field. Finally, the formula for Coulomb’s Law was presented and compared with that for gravitational force. Both forces are directly dependent on the magnitude of the property of matter generating the force (mass for gravity and charge for electric force) and inversely proportional to distance squared. You’ll get math practice tomorrow with Coulomb’s Law so don’t forget your calculator.
Physical Science E reviewed their static electricity experiments and began to explore the concept of static charge in more detail. The property of charge was described and related to the production of electric forces and fields. Methods of charging neutral objects was discussed and the basic properties of the three main subatomic particles (protons, neutrons and electrons) were reviewed. Tomorrow, we’ll take a more quantitative look at electric forces and fields before moving on to electric current.
Physics F and G had a final discussion of their lab activities and then turned attention back to the properties of mirrors. Plane mirrors were reviewed and the characteristics of convex and concave mirrors were introduced. The rules for drawing ray diagrams were presented and students got some practice seeing how these diagrams verified the mirror equation.
Homework
Honors Physics A: Conceptual Challenge p. 545 and Chapter Review items #37-45
Physical Science B and E: None
Physics F and G: None
3/10/10
Seeing the Light
Honors Physics took time to review the assignments pertaining to reflection and mirrors. It would be prudent to start laying a foundation in the brain as to the types of images and sign conventions associated with flat, concave and convex mirrors. Makes problem solving a lot easier. Tomorrow, we take on color and polarization, then it’s off to refraction.
Physical Science B got a reminder about the importance of the MCAS exam in June and we then headed into a discussion of the nature of charge and static electricity. We discussed the concept of fundamental charge, the ability of charge to produce forces of attraction and repulsion and started to describe methods of generating a charge on a neutral object. Remember, charge is produced on objects by an imbalance of positives and negatives. The negatively-charged electrons are the particle that is in motion when an object acquires a charge. We’ll continue discussing methods of generating charge tomorrow and begin to assess how to quantify the size of the electric force generated by charged objects – Coulomb’s Law.
Physical Science E participated in a lab investigation about static charge and the forces that charged objects can produce. Students were able to charge objects through friction, conduction and induction and see how the subsequent forces were able to influence the motion of matter. Electric force behaves like any force, the amount of acceleration produced on an object is directly proportional to the size of the force and inversely proportional to the object’s mass. We’ll discuss the lab in more detail tomorrow and use it to highlight our discussion of charge and static electricity.
Physics F and G worked on completing their lab investigations. Groups finished up with data collection and/or worked on the data analysis and lab write up. Tomorrow, we discuss the behavior of light when it reflects off of curved mirrors.
Homework
Honors Physics A: None
Physical Science B: None
Physical Science E: Complete lab write up
Physics F and G: Complete lab write up
Physical Science B got a reminder about the importance of the MCAS exam in June and we then headed into a discussion of the nature of charge and static electricity. We discussed the concept of fundamental charge, the ability of charge to produce forces of attraction and repulsion and started to describe methods of generating a charge on a neutral object. Remember, charge is produced on objects by an imbalance of positives and negatives. The negatively-charged electrons are the particle that is in motion when an object acquires a charge. We’ll continue discussing methods of generating charge tomorrow and begin to assess how to quantify the size of the electric force generated by charged objects – Coulomb’s Law.
Physical Science E participated in a lab investigation about static charge and the forces that charged objects can produce. Students were able to charge objects through friction, conduction and induction and see how the subsequent forces were able to influence the motion of matter. Electric force behaves like any force, the amount of acceleration produced on an object is directly proportional to the size of the force and inversely proportional to the object’s mass. We’ll discuss the lab in more detail tomorrow and use it to highlight our discussion of charge and static electricity.
Physics F and G worked on completing their lab investigations. Groups finished up with data collection and/or worked on the data analysis and lab write up. Tomorrow, we discuss the behavior of light when it reflects off of curved mirrors.
Homework
Honors Physics A: None
Physical Science B: None
Physical Science E: Complete lab write up
Physics F and G: Complete lab write up
3/9/10
Without Bad Luck I'd Have No Luck At All
This weekend, the nicest of the year, was a total bust since I had a nasty cold and stayed indoors the whole time. My dogs are not happy with me at the moment and will likely exact their revenge in the near future…
Honors Physics reviewed Friday’s lab activity and then completed their discussion of mirrors. With mirrors, keep sign conventions in mind at all times with working with the mirror formula. Also, pay close attention when drawing ray diagrams for diverging mirrors or for converging mirrors when the object is within the mirror’s focal length. Those can get a little tricky if you’re not careful. Tomorrow, we’ll start with color and polarization and then its off to refraction.
Physical Science B and E endured their graded learning experience for sound and light. Tomorrow, we jump into the concepts of charge, electric potential energy and static electricity. E Block will conduct a lab investigation centered on static electricity and the forces produced when charged objects are brought together.
Physics F worked on their light lab investigations. Reflection by plane and curved mirrors was examined, as was the polarization of light and reflectivity of different surfaces and colors. Physics G worked on a reduced version of this lab, concentrating only on reflectivity and polarization. It was found that both color and texture affect reflectivity and that the intensity of light passing through a polarizer and analyzer could be predicted using Malus’s Law. For mirrors, plane mirrors verified the law of reflection and formed only virtual images, concave mirrors could form both real and virtual images and convex mirrors were, like plane mirrors, restricted to forming virtual images. A couple of groups in both blocks didn't get to finish collecting the data, so I'll allow some time at the beginning of class tomorrow for them to wind up their labs. The lab write ups will, therefore, not be due tomorrow.
Homework
Honors Physics A: None
Physical Science B: 16.1 Section Review, Chapter Review items # 13, 22, 29, 30
Physical Science E: Read lab protocol sheet and complete 16.1 Section Review and Chapter Review items #13, 22, 29, 30
Physics F: None
Physics G: None
Honors Physics reviewed Friday’s lab activity and then completed their discussion of mirrors. With mirrors, keep sign conventions in mind at all times with working with the mirror formula. Also, pay close attention when drawing ray diagrams for diverging mirrors or for converging mirrors when the object is within the mirror’s focal length. Those can get a little tricky if you’re not careful. Tomorrow, we’ll start with color and polarization and then its off to refraction.
Physical Science B and E endured their graded learning experience for sound and light. Tomorrow, we jump into the concepts of charge, electric potential energy and static electricity. E Block will conduct a lab investigation centered on static electricity and the forces produced when charged objects are brought together.
Physics F worked on their light lab investigations. Reflection by plane and curved mirrors was examined, as was the polarization of light and reflectivity of different surfaces and colors. Physics G worked on a reduced version of this lab, concentrating only on reflectivity and polarization. It was found that both color and texture affect reflectivity and that the intensity of light passing through a polarizer and analyzer could be predicted using Malus’s Law. For mirrors, plane mirrors verified the law of reflection and formed only virtual images, concave mirrors could form both real and virtual images and convex mirrors were, like plane mirrors, restricted to forming virtual images. A couple of groups in both blocks didn't get to finish collecting the data, so I'll allow some time at the beginning of class tomorrow for them to wind up their labs. The lab write ups will, therefore, not be due tomorrow.
Homework
Honors Physics A: None
Physical Science B: 16.1 Section Review, Chapter Review items # 13, 22, 29, 30
Physical Science E: Read lab protocol sheet and complete 16.1 Section Review and Chapter Review items #13, 22, 29, 30
Physics F: None
Physics G: None
3/5/10
Happy FryDay
Honors Physics conducted a lab investigation centering on mirrors, reflection and polarization. Plane mirrors were investigated to validate the law of reflection and the pattern of image formation was described. Students then worked with convex and concave mirrors to assess what types of images these mirrors could form. For polarization, students examined Malus’s law, which allows one to predict the intensity of light passing through a polarizing filter system based on the angle of the polarizer. Students found that light intensity decreases steadily as one polarizer is rotated with respect to a second, with maximum extinction occurring when the polarizers are at 90 degrees. The overall data supported Malus’s law, which further supports the model of light as a transverse wave.
Physical Science B and Physical Science E reviewed for Monday’s exam on sound and light. We walked through the chapter, reviewed study materials and answered any questions that still plagued folks. Starting Tuesday – Electricity!
Physics F and G began their discussion of light and reflection. We described the dual nature of light and then moved to the basics of reflection. Specular and diffuse reflection were contrasted and described based on the law of reflection. The, attention turned to plane mirrors and the formation of virtual images. On Monday, G Block will engage in a lab activity that will allow them to explore both plane and curved mirrors, while F Block begins to discuss how curved mirrors produce images.
Homework
Honors Physics A: Complete lab write up, the 14.3 Section Review and Practice 14B (only do ray diagram for first two problems)
Physical Science B: Study for sound and light exam
Physical Science E: Complete review packet and study for sound and light exam
Physics F: None
Physics G: Read lab protocol sheets
Physical Science B and Physical Science E reviewed for Monday’s exam on sound and light. We walked through the chapter, reviewed study materials and answered any questions that still plagued folks. Starting Tuesday – Electricity!
Physics F and G began their discussion of light and reflection. We described the dual nature of light and then moved to the basics of reflection. Specular and diffuse reflection were contrasted and described based on the law of reflection. The, attention turned to plane mirrors and the formation of virtual images. On Monday, G Block will engage in a lab activity that will allow them to explore both plane and curved mirrors, while F Block begins to discuss how curved mirrors produce images.
Homework
Honors Physics A: Complete lab write up, the 14.3 Section Review and Practice 14B (only do ray diagram for first two problems)
Physical Science B: Study for sound and light exam
Physical Science E: Complete review packet and study for sound and light exam
Physics F: None
Physics G: Read lab protocol sheets
3/4/10
This is Too Cool
Popular Science has scanned in its back issues (its been around 137 years, so that's a lot of titles) and has made the archive FREE to search online! You can't just browse issues, yet, but when you do a search and choose an article to read, you get the whole issue, so you can look through the whole thing. This is an amazing resource of scientific initiative - bookmark the site. NOW!Enough is Enough
Though it was just a little and it didn't stick, seeing snow today was not a happy-making experience. Time for sunshine. Buckets and buckets of sunshine...
Honors Physics went over yesterday’s sound exam and then moved into the light. We started out by describing the general properties of light (as per the wave model), the components of the electromagnetic spectrum, Huygen’s ideas about light propagation, reflection and plane mirrors. A lot of this was covered back in the vibrations and waves chapter, so we were able to move through that material at a pretty fast clip. Tomorrow, you will get a chance to work with plane mirrors and also with convex and concave mirrors. We said that plane mirrors make virtual images that are the same size and orientation as the object and appear as far behind the mirror as the object is in front of the mirror. It is a different ballgame with curved mirrors….
Physical Science B conducted a lab investigation with lenses to study refraction, image formation and magnification. Using a biconvex lens, students made real and virtual images, determined the focal length of the lens and calculated magnification for the various images formed. The results of the lab were good! Students were clearly able to see the pattern of image formation as an object moved closer and closer to a lens and the result when an object was placed at the focal length and within the focal length. Further, the calculate focal lengths coincided nicely with that experimentally determined at the beginning of the investigation. We’ll go over the lab tomorrow, so make sure you have completed the lab write up. Time will also be spent reviewing refraction and dispersion before starting the general chapter review in preparation for Monday’s exam.
Physical Science E discussed dispersion of light by prisms and raindrops. Rainbow formation was explained, as were the variations of the simple rainbow: multiple rainbows, full rainbows and moonbows We then turned attention to starting the review for Monday’s exam on sound and light. Make sure to come with any final questions tomorrow so that we can get you squared away before the test.
Physics F and G spent time correcting their sound exams. Light and reflection begins tomorrow…
Homework
Honors Physics A: None
Physical Science B: Complete lab write up and review worksheet packet
Physical Science E: None
Physics F and G: Complete test corrections
Honors Physics went over yesterday’s sound exam and then moved into the light. We started out by describing the general properties of light (as per the wave model), the components of the electromagnetic spectrum, Huygen’s ideas about light propagation, reflection and plane mirrors. A lot of this was covered back in the vibrations and waves chapter, so we were able to move through that material at a pretty fast clip. Tomorrow, you will get a chance to work with plane mirrors and also with convex and concave mirrors. We said that plane mirrors make virtual images that are the same size and orientation as the object and appear as far behind the mirror as the object is in front of the mirror. It is a different ballgame with curved mirrors….
Physical Science B conducted a lab investigation with lenses to study refraction, image formation and magnification. Using a biconvex lens, students made real and virtual images, determined the focal length of the lens and calculated magnification for the various images formed. The results of the lab were good! Students were clearly able to see the pattern of image formation as an object moved closer and closer to a lens and the result when an object was placed at the focal length and within the focal length. Further, the calculate focal lengths coincided nicely with that experimentally determined at the beginning of the investigation. We’ll go over the lab tomorrow, so make sure you have completed the lab write up. Time will also be spent reviewing refraction and dispersion before starting the general chapter review in preparation for Monday’s exam.
Physical Science E discussed dispersion of light by prisms and raindrops. Rainbow formation was explained, as were the variations of the simple rainbow: multiple rainbows, full rainbows and moonbows We then turned attention to starting the review for Monday’s exam on sound and light. Make sure to come with any final questions tomorrow so that we can get you squared away before the test.
Physics F and G spent time correcting their sound exams. Light and reflection begins tomorrow…
Homework
Honors Physics A: None
Physical Science B: Complete lab write up and review worksheet packet
Physical Science E: None
Physics F and G: Complete test corrections
3/3/10
Halfway to Friday
Honors Physics, Physics F and G all suffered through exams in the area of sound. Tomorrow, each class begins their unit on light with an over view of light and reflection. We’ll hit refraction and lenses in the next chapter, but will likely hop over diffraction and interference to make sure that we have sufficient time for electricity and magnetism.
Physical Science B completed their sound and light material with a discussion of refraction, lenses, dispersion and prisms. A refraction tank was used to demonstrate the diffraction of light as it passed between air and water and how light incident at an angle greater than the critical angle displayed total internal reflection. We looked at a natural fiber-optic material (ulexite) and discussed the use of fiber optics in the communications industry. Lastly, we described how prisms promoted dispersion and how water droplets in the atmosphere, functioning as prisms, create rainbows. Tomorrow, a lab on lenses, magnification and image formation.
Physical Science E had about the same day as B block, but did not make it as far as full coverage of prisms and dispersion. We’ll complete that discussion tomorrow and you will get to see rainbow formation by prisms. We’ll start our sound and light review, which we will complete on Friday in preparation for Monday’s exam.
Homework
Honors Physics A: 14.2 Section Review and Chapter Review items #6, 8, 12
Physical Science B: Read lab activity p. 524-525
Physical Science E: 15.4 Section Review
Phsyics F and G: Chapter Review #1-13
Physical Science B completed their sound and light material with a discussion of refraction, lenses, dispersion and prisms. A refraction tank was used to demonstrate the diffraction of light as it passed between air and water and how light incident at an angle greater than the critical angle displayed total internal reflection. We looked at a natural fiber-optic material (ulexite) and discussed the use of fiber optics in the communications industry. Lastly, we described how prisms promoted dispersion and how water droplets in the atmosphere, functioning as prisms, create rainbows. Tomorrow, a lab on lenses, magnification and image formation.
Physical Science E had about the same day as B block, but did not make it as far as full coverage of prisms and dispersion. We’ll complete that discussion tomorrow and you will get to see rainbow formation by prisms. We’ll start our sound and light review, which we will complete on Friday in preparation for Monday’s exam.
Homework
Honors Physics A: 14.2 Section Review and Chapter Review items #6, 8, 12
Physical Science B: Read lab activity p. 524-525
Physical Science E: 15.4 Section Review
Phsyics F and G: Chapter Review #1-13
3/2/10
A Sound Review
Honors Physics spent the period reviewing for tomorrow’s exam for sound. The mixed review worksheet was covered and students will turn it in tomorrow, so that they have it as a study resource tonight. Thursday – Light!
Physical Science B reviewed ideas about reflection and color and began to work through the concept of refraction. We will get into refraction more deeply tomorrow and begin a discussion of lenses. Thursday’s lab investigation will target image formation by lenses and should leave us with a little time to review the lab and refraction, in general. Friday, dispersion and a basic review. Monday – exam.
Physical Science E went over yesterday’s lab activity and then took time to review basic ideas about light and reflection. Tomorrow, we will begin our discussion of refraction and total internal reflection. Then, we tackle lenses and prisms. Then…review. Then…..Exam!
Physics F and G went over their mixed review worksheets and then proceeded to crawl through the chapter, highlighting important concepts and review problem solving techniques. Tomorrow, exam. Thursday, starting light and reflection.
Homework
Honors Physics A, Physics F and G: Study for exam
Physical Science B and E: None
Physical Science B reviewed ideas about reflection and color and began to work through the concept of refraction. We will get into refraction more deeply tomorrow and begin a discussion of lenses. Thursday’s lab investigation will target image formation by lenses and should leave us with a little time to review the lab and refraction, in general. Friday, dispersion and a basic review. Monday – exam.
Physical Science E went over yesterday’s lab activity and then took time to review basic ideas about light and reflection. Tomorrow, we will begin our discussion of refraction and total internal reflection. Then, we tackle lenses and prisms. Then…review. Then…..Exam!
Physics F and G went over their mixed review worksheets and then proceeded to crawl through the chapter, highlighting important concepts and review problem solving techniques. Tomorrow, exam. Thursday, starting light and reflection.
Homework
Honors Physics A, Physics F and G: Study for exam
Physical Science B and E: None
3/1/10
A Quiet Monday
What can one say about a day like Friday? Pretty much everyone had a horror story about power outages, property damage or overall chaos to describe. Thankfully, folks are in the process of getting back to normal and we got an unexpected 3-day weekend as a bonus.
Honors Physics finished up their sound material with a discussion of beats. Alternating areas on constructive and destructive interference produced by waves of different frequencies arriving at the ear at the same time. By counting the beat frequency, one can determine how many hertz the notes are apart. Time was given in class to work on the mixed review sheet for the chapter in preparation for tomorrow’s exam review. Bring all questions with you tomorrow as we prepare for Wednesday’s sound exam.
Physical Science B watched a video on color and light that nicely summarized the light topics to date. Tomorrow, we’ll go over the homework for reflection and color and then turn out attention to refraction and diffraction.
Physical Science E conducted their lab investigation on light reflectivity, polarization and intensity. As for B Block, the data demonstrated that color and texture have an effect on reflectivity, polarizing filters show maximum reduction in light intensity when oriented at 90 degrees to each other and light intensity decreases with distance with an inverse-square relationship. Tomorrow, we discuss the lab and then move on to refraction and diffraction.
Physics F and G reviewed harmonics and beats and then worked on review material for the chapter. Tomorrow – full period exam review. Wednesday – exam. Thursday – moving on to light and reflection.
Homework
Honors Physics A: Complete mixed review worksheet
Physical Science B: Complete 15.3 Section Review, Math Skills p. 519 and Chapter Review items #22-25
Physical Science E: Complete lab write up
Physics F and G: Complete mixed review worksheet
Honors Physics finished up their sound material with a discussion of beats. Alternating areas on constructive and destructive interference produced by waves of different frequencies arriving at the ear at the same time. By counting the beat frequency, one can determine how many hertz the notes are apart. Time was given in class to work on the mixed review sheet for the chapter in preparation for tomorrow’s exam review. Bring all questions with you tomorrow as we prepare for Wednesday’s sound exam.
Physical Science B watched a video on color and light that nicely summarized the light topics to date. Tomorrow, we’ll go over the homework for reflection and color and then turn out attention to refraction and diffraction.
Physical Science E conducted their lab investigation on light reflectivity, polarization and intensity. As for B Block, the data demonstrated that color and texture have an effect on reflectivity, polarizing filters show maximum reduction in light intensity when oriented at 90 degrees to each other and light intensity decreases with distance with an inverse-square relationship. Tomorrow, we discuss the lab and then move on to refraction and diffraction.
Physics F and G reviewed harmonics and beats and then worked on review material for the chapter. Tomorrow – full period exam review. Wednesday – exam. Thursday – moving on to light and reflection.
Homework
Honors Physics A: Complete mixed review worksheet
Physical Science B: Complete 15.3 Section Review, Math Skills p. 519 and Chapter Review items #22-25
Physical Science E: Complete lab write up
Physics F and G: Complete mixed review worksheet
2/25/10
And More Rain
I am considering building an ark...I already have two dogs...
Honors Physics discussed yesterday's lab and any discrepancies in data that they might have noticed. We then went over the homework questions/problems and the open-book vibrations and waves quiz. Finally, it was time for new material and that material was harmonics. For musical instruments, harmonics produce the characteristic sounds on instruments and the overall quality of the sound. The overtones for the tuning fork that you documented in your lab were harmonics of the tuning fork's fundamental frequency. Stringed instruments and pipes open at both ends are able to produce a full harmonic series. Pipes closed at one end are restricted to the odd harmonics. Additionally, these instruments have, for their fundamental frequencies, corresponding wavelengths that are 4x the length of the vibrating air column. The stringed instruments and pipes open at both ends have wavelengths for their fundamental frequencies that are 2x the length of the vibrating media. The difference is that for strings and open pipes, each end of the vibrating material is identical - both nodes or both antinodes. For a pipe closed at one end, one terminus is a node and the other is an antinode. Be sure to have these distinctions well in mind for next week's test. Tomorrow - beats!
Physical Science B examined mirrors. Plane, convex and concave - mirrors rely on reflection for image formation. Plane and convex mirrors only form virtual images but concave mirrors can form both virtual and real images. Students had the chance to handle each type of curved mirror and examine a large convex mirror that had been used as a security mirror. A little bit of color was discussed, but more of that will be had during tomorrow's film and in class on Monday.
Physical Science E watched their light and color film - fairly basic but covered all the high points. We will review the basics of light and color tomorrow and begin to discuss another behavior of light - refraction. On Monday, you'll conduct a few lab investigations on properties of light: reflectivity, polarization and intensity.
Physics F spent time finalizing their discussion of sound. The concept of harmonics was defined and harmonic series for various types of instruments was discussed. The role of harmonics in producing the characteristic sound of different instruments was examined, as was the importance of harmonics in producing enjoyable music. Then, the phenomenon of beats was introduced - alternating constructive and destructive interference that can be used to determine how out of tune is a particular instrument. Tomorrow, a series of lab investigations on properties of sound.
Physics G conducted their sound lab investigations today. The speed of sound was determined for room temperature air and for heated air. Then, the sound profile for tuning forks, the human voice and a computer-generated tone dialer was examined. Tuning forks produced fairly clear sine curves when lightly struck and more complex waveforms when firmly struck. This was due to the production of overtones (harmonics). The audio profile for the human voice was also complex. Humans do not emit a single note when they speak or sing, there are other tones blended in that were demonstrated on the computer. The tone pattern for the tone dialer is designed that each number is represented by two tones: a row tone and a column tone. In this way, note frequency combinations generate numerical information for the phone company. Tomorrow, we'll discuss the lab and take time to more closely examine those overtones in our discussion of harmonics.
Homework
Honors Physics A: None
Physical Science B: None
Physical Science E: Chapter Review items #22-25 and p. 519 #1-3
Physics F: Read lab protocol sheet and complete Chapter Review items #29-38
Physics G: Complete lab write up
Honors Physics discussed yesterday's lab and any discrepancies in data that they might have noticed. We then went over the homework questions/problems and the open-book vibrations and waves quiz. Finally, it was time for new material and that material was harmonics. For musical instruments, harmonics produce the characteristic sounds on instruments and the overall quality of the sound. The overtones for the tuning fork that you documented in your lab were harmonics of the tuning fork's fundamental frequency. Stringed instruments and pipes open at both ends are able to produce a full harmonic series. Pipes closed at one end are restricted to the odd harmonics. Additionally, these instruments have, for their fundamental frequencies, corresponding wavelengths that are 4x the length of the vibrating air column. The stringed instruments and pipes open at both ends have wavelengths for their fundamental frequencies that are 2x the length of the vibrating media. The difference is that for strings and open pipes, each end of the vibrating material is identical - both nodes or both antinodes. For a pipe closed at one end, one terminus is a node and the other is an antinode. Be sure to have these distinctions well in mind for next week's test. Tomorrow - beats!
Physical Science B examined mirrors. Plane, convex and concave - mirrors rely on reflection for image formation. Plane and convex mirrors only form virtual images but concave mirrors can form both virtual and real images. Students had the chance to handle each type of curved mirror and examine a large convex mirror that had been used as a security mirror. A little bit of color was discussed, but more of that will be had during tomorrow's film and in class on Monday.
Physical Science E watched their light and color film - fairly basic but covered all the high points. We will review the basics of light and color tomorrow and begin to discuss another behavior of light - refraction. On Monday, you'll conduct a few lab investigations on properties of light: reflectivity, polarization and intensity.
Physics F spent time finalizing their discussion of sound. The concept of harmonics was defined and harmonic series for various types of instruments was discussed. The role of harmonics in producing the characteristic sound of different instruments was examined, as was the importance of harmonics in producing enjoyable music. Then, the phenomenon of beats was introduced - alternating constructive and destructive interference that can be used to determine how out of tune is a particular instrument. Tomorrow, a series of lab investigations on properties of sound.
Physics G conducted their sound lab investigations today. The speed of sound was determined for room temperature air and for heated air. Then, the sound profile for tuning forks, the human voice and a computer-generated tone dialer was examined. Tuning forks produced fairly clear sine curves when lightly struck and more complex waveforms when firmly struck. This was due to the production of overtones (harmonics). The audio profile for the human voice was also complex. Humans do not emit a single note when they speak or sing, there are other tones blended in that were demonstrated on the computer. The tone pattern for the tone dialer is designed that each number is represented by two tones: a row tone and a column tone. In this way, note frequency combinations generate numerical information for the phone company. Tomorrow, we'll discuss the lab and take time to more closely examine those overtones in our discussion of harmonics.
Homework
Honors Physics A: None
Physical Science B: None
Physical Science E: Chapter Review items #22-25 and p. 519 #1-3
Physics F: Read lab protocol sheet and complete Chapter Review items #29-38
Physics G: Complete lab write up
2/24/10
Raining Cats and Dogs
We better have good flowers this spring to compensate for all this rain...
Honors Physics conducted a series of lab investigations on sound. The first experiment allowed students to determine the speed of sound at room temperature and compare that to the speed of sound in heated air. Based on kinetic theory, we would expect that the speed of sound in the heated air would be greater due to the greater velocity of the air particles, and this was found to be the case. The next set of experiments dealt with properties of sound produced by different sources. A softly and firmly struck tuning fork demonstrated the fundamental tone and the fundamental tone and overtones, respectively. The human voice is not like a tuning fork. A variety of tones are produced with each vocalization and this makes the more complex waveform that you saw on the computer. The final experiment let students determine how tones are used by a telephone to send number information. On a touch pad, there are column and row frequencies. Each number is designated by two tones – the one corresponding to its row and the one corresponding to its column. Tomorrow, we’ll go over the labs in more detail and then begin our discussion of musical instruments and harmonics.
Physical Science B discussed their lab and took time to make a few corrections to some calculations. Attention was then turned to reflection and plane mirrors. the law of reflection holds regardless of surface type, but different surfaces vary in their reflective abilities. We contrasted diffuse and specular reflection and used the plane mirror as an exemplar for how to analyze reflection on smooth surfaces. Tomorrow, curved mirrors and color!
Physical Science E took time to review the basic principles of reflection and plane mirrors and then extended this to curved mirrors. Based on mirror type and distance of object to mirror, we have the possibility of forming both real and virtual images. We then turned attention to color and discussed the role of reflection in color production. Tomorrow, we will watch a video that summarizes basic properties of light and does a nice job of explaining additive and subtractive color systems.
Physics F and G discussed the factors that affect how loud sounds seem to people. We disentangled the relationships between intensity, relative intensity, loudness and the decibel scale. We also took time to discuss the effects of sound on humans and the topic of noise pollution. Tomorrow, G Block will conduct their lab investigations for sound and F block will move into the area of harmonics.
Homework
Honors Physics A: Complete lab write up
Physical Science B: None
Physical Science E: None
Physics F: Conceptual Challenge p. 502 and the 13.3 Section Review
Physics G: Read lab protocol sheet and complete the 13.3 Section Review and Conceptual Challenge (p. 502) for Friday
Honors Physics conducted a series of lab investigations on sound. The first experiment allowed students to determine the speed of sound at room temperature and compare that to the speed of sound in heated air. Based on kinetic theory, we would expect that the speed of sound in the heated air would be greater due to the greater velocity of the air particles, and this was found to be the case. The next set of experiments dealt with properties of sound produced by different sources. A softly and firmly struck tuning fork demonstrated the fundamental tone and the fundamental tone and overtones, respectively. The human voice is not like a tuning fork. A variety of tones are produced with each vocalization and this makes the more complex waveform that you saw on the computer. The final experiment let students determine how tones are used by a telephone to send number information. On a touch pad, there are column and row frequencies. Each number is designated by two tones – the one corresponding to its row and the one corresponding to its column. Tomorrow, we’ll go over the labs in more detail and then begin our discussion of musical instruments and harmonics.
Physical Science B discussed their lab and took time to make a few corrections to some calculations. Attention was then turned to reflection and plane mirrors. the law of reflection holds regardless of surface type, but different surfaces vary in their reflective abilities. We contrasted diffuse and specular reflection and used the plane mirror as an exemplar for how to analyze reflection on smooth surfaces. Tomorrow, curved mirrors and color!
Physical Science E took time to review the basic principles of reflection and plane mirrors and then extended this to curved mirrors. Based on mirror type and distance of object to mirror, we have the possibility of forming both real and virtual images. We then turned attention to color and discussed the role of reflection in color production. Tomorrow, we will watch a video that summarizes basic properties of light and does a nice job of explaining additive and subtractive color systems.
Physics F and G discussed the factors that affect how loud sounds seem to people. We disentangled the relationships between intensity, relative intensity, loudness and the decibel scale. We also took time to discuss the effects of sound on humans and the topic of noise pollution. Tomorrow, G Block will conduct their lab investigations for sound and F block will move into the area of harmonics.
Homework
Honors Physics A: Complete lab write up
Physical Science B: None
Physical Science E: None
Physics F: Conceptual Challenge p. 502 and the 13.3 Section Review
Physics G: Read lab protocol sheet and complete the 13.3 Section Review and Conceptual Challenge (p. 502) for Friday
2/23/10
Sound and Light
Honors Physics continued to explore sound with a discussion of sound intensity and loudness. Intensity is a function purely of the wave and distance from the source; loudness references how we perceive the intensity. We discussed the decibel scale and the effects of sounds in the “loud” range and beyond on humans. Attention then turned to the concept of resonance – a frequency-specific forced vibration in an object. We looked at some examples of resonance and will dig into this concept more deeply as we begin to study musical instruments. Tomorrow’s lab will allow you to work with basic concepts of sound, such as speed and features of the wave, and, if time permits, let’s you gain insight into how a touch-tone phone conveys information through tones.
Physical Science B investigated light in a series of three experiments. One experiment focused on reflectivity of light and few were surprised when dark colors and dull textures showed less reflectivity than lighter colors or shiny textures. The second experiment had students work with polarizing filters to document the transverse nature of light waves and to get an idea of how polarizing filters on cameras and polarizing sunglasses function to reduce glare. The final experiment targeted the inverse-square relationship associated with light intensity. As an observer moves away from a light source, the intensity drops quickly, as predicted by the formula: I = P/4πr2. We’ll discuss these labs in class tomorrow and move on to examining reflection of light in more depth.
Physical Science E began discussing behaviors of light, starting with reflection. When light meets an impenetrable boundary, it is either absorbed by the material or reflected off of the material. While there is no material that is a perfect absorber or reflector, most things lean heavily in one direction. We contrasted specular and diffuse reflection, used the law of reflection to predicted reflected angles based on angles on incidence and started to examine reflection by plane mirrors. We’ll add curved mirrors to the list tomorrow, along with color.
Physics F and G embarked on their study of sound by revisiting basic properties of longitudinal and mechanical waves and then applying some sound-specific vocabulary to these concepts. Hearing and vocalization in various species was examined and the use of ultrasonic waves by humans and animals was described. Tomorrow, we continue on with sound, concentrating on loudness and resonance.
Homework\
Honors Physics A: Practice 13A #1-3, 13.2 Section Review
Physical Science B: Complete lab write up
Physical Science E: 15.3 Section Review
Physics F and G: Chapter 13 Review #21-23, 25, 26
Physical Science B investigated light in a series of three experiments. One experiment focused on reflectivity of light and few were surprised when dark colors and dull textures showed less reflectivity than lighter colors or shiny textures. The second experiment had students work with polarizing filters to document the transverse nature of light waves and to get an idea of how polarizing filters on cameras and polarizing sunglasses function to reduce glare. The final experiment targeted the inverse-square relationship associated with light intensity. As an observer moves away from a light source, the intensity drops quickly, as predicted by the formula: I = P/4πr2. We’ll discuss these labs in class tomorrow and move on to examining reflection of light in more depth.
Physical Science E began discussing behaviors of light, starting with reflection. When light meets an impenetrable boundary, it is either absorbed by the material or reflected off of the material. While there is no material that is a perfect absorber or reflector, most things lean heavily in one direction. We contrasted specular and diffuse reflection, used the law of reflection to predicted reflected angles based on angles on incidence and started to examine reflection by plane mirrors. We’ll add curved mirrors to the list tomorrow, along with color.
Physics F and G embarked on their study of sound by revisiting basic properties of longitudinal and mechanical waves and then applying some sound-specific vocabulary to these concepts. Hearing and vocalization in various species was examined and the use of ultrasonic waves by humans and animals was described. Tomorrow, we continue on with sound, concentrating on loudness and resonance.
Homework\
Honors Physics A: Practice 13A #1-3, 13.2 Section Review
Physical Science B: Complete lab write up
Physical Science E: 15.3 Section Review
Physics F and G: Chapter 13 Review #21-23, 25, 26
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