Angular Momentum Conservation -- Rope Problem

AI Thread Summary
In the scenario of a man swinging on a rope in space, his angular momentum is conserved while he climbs the rope at a constant speed. As he climbs, the component of his velocity becomes non-perpendicular to the rope, allowing the tension force to do work and increase his tangential speed. Despite this increase in speed, the force remains directed toward the pivot, resulting in no net torque. Thus, angular momentum conservation holds true while allowing for changes in speed. This illustrates the relationship between climbing, tension, and angular momentum in rotational motion.
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Say there is a man swinging in space on a rope attached to a pivot. The man is rotating at some constant angular speed w.

Now he climbs up the rope at some constant speed v. Apparently the angular momentum is conserved. As a result his speed increases. However, how does his speed increase if there is no force in the tangential direction, because angular momentum is conserved and there can't be a force here as it would cause torque.I solved it
 
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Do you wish to share your solution?
 
pixel said:
Do you wish to share your solution?

Basically as soon as the man starts climbing there is a component of velocity that is no longer perpendicular to the rope since he is climbing upward. As a result the tension force can do work and increase speed, however though the speed increases the force still points toward the origin and there is therefore no net torque.
 

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