Torque and Throwing A Ball
Country: New Zealand
Date: Summer 2013
What is the science behind a person throwing a tennis ball? Does length of the arm and the height of the thrower affect the distance a ball can be thrown?
Thanks for the question. The science behind throwing a tennis ball is quite complicated and involves physics, air resistance, and biology. Yes, the length of the arm and how strong the arm is do affect the distance a ball is thrown. The taller a person, the farther a ball can be thrown, assuming everything else is the same.
I hope this helps. Please let me know if you have more questions.
There may be several effects at work at the same time. But, any ball that is thrown really has motion in two directions (or at least we can think of it that way). The ball flies parallel to the ground, but it also looks like its falling (if it did not fall due to gravity there would be an awfully large number of balls just hovering around and you would never have to bend over to pick one up).
Together these two motions add up to the arching track thrown balls seem to follow.
Since the ball goes horizontally until it hits the ground, the higher it starts out, the longer it take to fall to the ground. The longer it flies, the further it will go. One point for a taller person.
If the thrower also lets go of the ball at the top of their throw, a longer arm would help in the same way. Two pints for tall people with long arms!
And, assuming that the taller thrower can throw just as hard and the shorter person, the ball will be going faster with a longer arm (just like the outside of a carousel moves faster that the middle). Tall people 3 points, little folks nil.
Hope this helps. If you nee me to make it any clearer, write back.
Tulsa, Oklahoma, USA
Yes. The force of the ball is related to the length of the arm by the torque. T=r*F where r is radius.
The height of the person will effect the distance thrown by effecting the time before the ball reaches the ground. More height means longer to reach the ground means longer distance traveled.
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Update: November 2011