Unit 8- Work & Energy & Power

Today we learned about powaaahhhhhh, but before that we learned how to graph energy. Energy graphs are different from distance vs. time graphs, velocity vs. time graph or acceleration vs. time. They aren't line graphs, they are bar graphs. On these graphs you have spots for gravitational potential energy, spring potential energy, kinetic energy, work and total energy. You have to read the word problems, and figure out which energies are present then graph them out.

We also reviewed work. Work is a change in energy. Work= force x distance and force= mass x gravity.The unit for work is joules. Energy is always conserved so you can convert work into other things like potential spring energy, gravitational potential energy, and kinetic energy. This is proven by the law of conservation of energy. For these problems use the equation Ein=Eout 

This photo represents a lab that we did in class today that involved power. We had to choose a person, get their mass, figure out the distance of the stairs and then time the person running up the stairs. From this information we could figure out their force, their work, and their power. 

Power is the rate at which work is done. Power= change in energy/ change in time= work/ time. The unit for power is watts or (joules/seconds). Through a lab we learned that a larger mass has a larger power.