Physics of Golf: Angular Momentum & External Torque

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The discussion centers on the angular momentum of a golf ball putted past a hole, moving at constant velocity and ignoring friction. It is established that the angular momentum about the hole remains constant, although its direction changes due to external torque. The participants emphasize the importance of understanding the relationship between angular momentum and the forces acting on the ball, noting that all forces must sum to zero for constant velocity. The definition of angular momentum is highlighted, specifically the equation L = r x p, where r is the position vector and p is the momentum. Overall, the conversation delves into the physics principles governing the motion of the golf ball in relation to angular momentum and torque.
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A golf ball is putted too fast and rolls past the hole in a straight line, coming at closest approach to a distance d from the hole. Ignore friction and assume that golf ball moves at constant velocity.
What is the angular momentum of the golf ball about the hole?
Is the angular momentum constant about this point?

I believe that the angular momentum is constant but its direction changes due to an external torque. Yet the equation to use is beyond me could it be d(theta)=dL/L?
 
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Actually... When we say a golf ball has a constant velocity, all the forces must add up to be zero.

Start with that by drawing components then doing a sum in the X and Y directions.
 
sauri said:
What is the angular momentum of the golf ball about the hole?
Consider the definition of the angular momentum of a particle:
\vec{L} = \vec{r} \times \vec{p}
 
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