Winding Down with Work

Physics D had their review for their work and energy exam, after reviewing specifically the topic of power. Tomorrow, we'll be working on a lab that has you investigate the properties of simple machines and how they manipulate the force and distance components of work. There should be time during lab, if necessary, for you to ask individual questions in preparation Monday's exam. Physics F conducted the lab investigation yesterday and we went over it at the start of class today. The lab material won't be on Monday's test (we'll save that for later when we discuss simple machines and torque), but our discussion about power will be. Remember that power is the rate at which work is done or energy is transformed and that broad definition means it can be approached in a variety of ways mathematically. We looked at the possible ways to calculate power associated with a situation and the problems you're working on tonight will give you practice using those techniques. Tomorrow, a review of Chapter 5 in preparation for Monday's exam.

Honors Physics conducted an investigation that focused on how inclined planes and simple/multiple pulleys manipulated force and distance to make work easier. Folks saw that as a machine multiplied effort force, it did so at the expense of distance and experienced a loss of useful energy. There is always a cost to using a machine, but since it makes work easier to do, we pay that cost gladly. The lab material won't be on tomorrow's exam, but do remember to have the lab packet completed by Monday.

Intro Physics finished their lab on density. Density, as you found, is independent of the size and shape of the object. Your graphs of mass vs. volume, documented a direct, linear relationship, the slope of which was the material's density. As you add mass, it needs more space and that relationship is fixed for solids and liquids. Gases is another story and we'll discuss that when we look at gases specifically. Finish up the calculations, questions, graphs and slope calculations for your lab tonight so we can discuss your results in detail tomorrow.