Pedro Martinez, Boston Red Sox
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There are plenty of forces in baseball that take affect.
In order to strike out the batter, the pitcher has to apply a force to the ball. The speed and velocity of the ball is then determined by the pitcher. A pitcher can apply many different types of forces that cause the ball to do different unique things. For instance a pitcher can apply a force to the ball so that it sinks right as it gets close to the batter, making the batter think he will be able to swing at it. This is known as the curve ball. The pitchers arm acts like a lever giving him mechanical advantage allowing him to increase his force. Some pitchers can pitch a ball consistently at 99mph.
In catching the ball (out in the field) you are anticipating where that ball will land. You have to position yourself so that you can catch it. Since the ball travels in a parabola (do to gravity) you need to position your self half the distance of the maximum height. When doing this a baseball player is calculating the angle of where the ball will land.
Various catcher gloves used to stop large forces
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The catcher that sits behind home plate has to control the force that the pitcher provides. This catcher stops 100 mph balls instantly. The force has to go somewhere. Where does it go? A lot of this force disburses into the glove, and less into the hand and arm. Years of training can teach you how to catch a fast ball with less pain. However sometimes a fast ballís forces go straight into the hand and have caused some catcherís hands to break. After a catcher has played a game they always ice down their hand from the reaction of stopping a large force.
Another force that a catcher faces are runners. A runner, like this one has a force and he thinks nothing is going to get in the way of him touching home plate but the force of the catcher sometimes stops him.

Copyright © 2002 Jonathan R. Drobnis
Last modified: November 27, 2002
Physics 211