Couple of v. important problems

[Clef]

there's a couple of problems that i have to give in at the end of this lunctime that i just can't work out how to approach or what formulas to use:

1. A 70g tennis ball falls 2 meters and bounces back up to a height of 1.9 meters
(a)How much kinetic energy does the tennis ball have?

(b)the ball compresses 10cm for a period of 2 seconds, what is the kinetic energy of the ball during this time?

2) a car is traveling at 75km/h up a hill. Assuming that gravity =9.8 ms-2, what is the maximum height that the car wil reach?

 

[Chi Meson]

there's a couple of problems that i have to give in at the end of this lunctime that i just can't work out how to approach or what formulas to use:

1. A 70g tennis ball falls 2 meters and bounces back up to a height of 1.9 meters
(a)How much kinetic energy does the tennis ball have?

Is the ball moving at the top of the bounce?

(b)the ball compresses 10cm for a period of 2 seconds, what is the kinetic energy of the ball during this time?

Is this really the question? How can a 7 cm diameter object compress 10 cm? Anyway, same analysis. Is the ball moving while it is compressed?

2) a car is traveling at 75km/h up a hill. Assuming that gravity =9.8 ms-2, what is the maximum height that the car wil reach?

By height, it means "altitude above starting position." Consider conservation of energy: KE becomes PE.