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Name: Douglas R.
Status: other
Age: $5
Location: N/A
Country: N/A
Date: 2000-2001

I am a pitcher and can throw the ball one hundred miles per hour. (Not really, but let us pretend.) Is it true that my hand -- at the moment of release -- must also be moving at that speed? A related question: When does the ball reach maximum speed? (I assume at the release point.)

Yes, if the ball moves at 100 miles per hour, your hand had to move that fast as well. And yes, the maximum velocity of the ball in the forward direction will be at the point of release. If you throw a pitch off the Empire State Building, it may accelerate to a very high speed in the downward direction, but its forward velocity will continuously decrease from the effect of wind resistance.

Richard E. Barrans Jr., Ph.D.
Assistant Director
PG Research Foundation, Darien, Illinois

Your hand, or at least your fingers, have to be moving at the same speed as the ball when you let go. At this point the ball has its maximum speed, and it slows down all the way to the catcher.

Tim Mooney

I assume that since there is nothing to accellerate the ball after it is released, the fastest speed is at the point of release. Your fingertips, relative to the ground, has to be moving at 100 mph.

-Wil Lam

Yes and Yes. Newton's Laws of motion require that the ball be at max. speed upon release. After release it can only change direction and slow down due to air resistance.

Vince Calder

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