Force and Momentum

Honors Physics began their discussion of momentum with an overview of impulse and the impulse-momentum theorem. I emphasized today and will reiterate it again to keep a close eye on the signs for velocity. Momentum is a vector, and takes the direction of the object’s velocity. Momentum change takes into account a change in both the direction and magnitude of the velocity, so watch closely how you set up your equations. Tomorrow’s lab activity will allow you to measure the impulse on an object and compare it to the change of momentum the object experiences. We’ll use a variety of elastic materials for your tests so that you can demonstrate and reflect upon the importance of choosing proper materials in construction, engineering and manufacturing.

Physical Science B conducted a lab activity that allowed them to examine the relationship between depth and fluid pressure. As we discussed in class, with greater depth comes greater pressure in a body of fluid. For the same area (the opening of the tubing, in this case), greater depth means a greater weight of fluid pressing down on the mass. Voila! Greater pressure. The mathematical relationship that you worked out in the expression told you that the pressure change was constant – the relationship was linear – and that the equation of the line you derived matched the equation for pressure/depth that we worked with in class on Friday. Tomorrow, another aspect of forces generated by fluids: buoyancy.

Physical Science E went over their Pascal’s Principle homework problems and we reviewed Pascal’s Principle before moving on to the changes in fluid pressure with depth. Using last week’s lab as an example, we discussed the equation used to calculate fluid pressure at any depth in any fluid and worked on practice problems using this formula. We’ll go over those tomorrow and then move on to the concept of buoyancy.

Physics F and G worked on test corrections. Make sure for your corrections that you show all work and explain for questions why the correct answer is actually the correct choice. Some folks are getting a little lazy about doing their corrections and I am going to stop accepting corrections that are not submitted with the proper information. Same goes for homework – homework should be completed and show all work. A few people are trying to submit homework that does not show work and/or does not show the required corrections. That is going to come around to bite you, so get back on track, pronto!

Homework

Honors Physics: Read lab sheet
Physical Science B: Complete lab write up
Physical Science E: Pressure As a Function of Depth problem worksheet
Physics F and G: p. 233 #17-24