# physics

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A .15kg ball is dropped from a height of 14 m to the ground below, and hits the ground with a speed of 12 m/s.

With what speed would the ball have hit the ground if there were no air resistance?

How much work does the air resistance do on the ball?

• physics -

no resistance:
Vf=sqrt2gh

work air resistance did?
mgh-1/2 m 12^2=work done on air

Air resistance does not do work, it absorbs energy at best.

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