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CricK0es

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## Homework Statement

A baseball rests on a frictionless, horizontal surface. The bat has a length of 0.900m, a mas of 0.800kg, and its center of mass is 0.600m from the handle end of the bat (see figure below). The moment of inertia of the bat about its center of mass is 0.0530 kg.m^2. The bat is struck by a baseball traveling perpendicular to the bat. The impact applies an impulse

$$J= \int_{t1}^{t2} F dt$$

at a distance x from the handle end of the bat. What must x be so that the handle end of the bat remains at rest as the bat begins to move? (Hint: consider the motion of the center of mass and the rotation about the center of mass. Finc x so that these two motions combine to give v=0 for the end of the bat just after the collision. Also, remember that . The point on the bat you have located is called the center of percussion. Hitting a

pitched ball at the center of percussion of the bat minimizes the "sting" the batter experiences on the hands.

## Homework Equations

$$J= \int_{t1}^{t2} F dt$$

Standard equation for torque[/B]

## The Attempt at a Solution

This involves both translation and rotational steps. In order to make v = 0, the bat must move in such a way, so as to counteract the rotation. This isn't a homework question, just one I've found in a book and I'm unsure how to proceed. I would appreciate someone explaining how the answer of 0.710m is found. I have a class test in a few days and I want to try and cover as many of my bases as possible. Many thanks[/B]