A fast pitch softball player does a “windmill” pitch, illustrated in Figure P6.18. moving her hand through a circular arc to pitch a ball at 70 mph. The 0.19 kg ball is 50 cm from the pivot point at her shoulder. At the lowest point of the circle, the ball has reached its maximum speed.
Figure P6.18
a. At the bottom of the circle, just before the ball leaves her hand, what is its centripetal acceleration?
b. What are the magnitude and direction of the force her hand exerts on the ball at this point?
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