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A baseball player extends his arm straight up to catch a 145-g baseball moving horizontally at 42 m/s. It’s 63 cm from the player’s shoulder joint to the point the ball strikes his hand, and his arm remains stiff while it rotates about the shoulder during the catch. The player’s hand recoils 5.00 cm horizontally while he stops the ball. What average torque does the player’s arm exert on the ball?
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