Question

Doug is driving a golf ball off the tee. His downswing takes 0.50 s from the top of the swing until ball impact. At the top of the swing, the club's angular velocity is zero; at the instant of ball impact, the club's angular velocity is 30 rad/s. The swing moment of inertia of the club about the grip is 0.220 kg m2. What average torque does Doug exert on the golf club during the downswing?

Answer is 13.2 Nm

Answer 1

same equations like the previous one.
we will find the averaged torque by finding the averaged angular acceleration.

the angular velocity is given by:
w = <alpha> * t
were <alpha> is the averaged angular acceleration.
<alpha> = w/t = 60 rad/sec^2
now using newton's second law :

<torque> = I * <alpha>
<torque> = 0.22 * 60 = 13.2 Nm