# Physics

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I'm not sure how to do this problem

A 145-g baseball is droppexc from a tree 12.0 m above the ground. (a) Wtih what speed would it hit the ground if air resistance could be ignored? (b) If it actually hits the ground with a speed of 8.00 s^-1 m, what is the average force of air resistance exerted on it?

• Physics -

a. Use energy:
mgh=(1/2)mv²

b. Again, equate energy
(1/2)mv² - (1/2)m8² = F*12.0

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