Question

1. How do you calculate kinetic energy (what is the formula)
2. A 700-kg vehicle is traveling at a speed of 6 m/s. How much kinetic energy does it have?
3. Two rocks of different masses are rolling down a hill at the same speed. Which rock (small one or big one) would have more kinetic energy?
4. Two rocks of same mass are rolling down a hill at different speeds (one faster than the other). Which rock would have more kinetic energy?

Answer 1

Well, if it is a moving mass it is (1/2) m v^2
if it is a rotating body with moment of inertia I it is (1/2) I omega^2

Answer 2

(1/2) 700 (36)

Answer 3

Same speed? The one with more mass and same v has more (1/2) m v^2
(we seem to be ignoring the rotational kinetic energy, probably the next chapter)

Answer 4

At this point if you can not get the last one I have failed totally.