Is torque required to change angular momentum?

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Torque is required to change angular momentum, as indicated by the relationship τ = Iα, where zero torque results in no change in angular speed. This aligns with Newton's first law of motion in advanced physics contexts. Some argue that internal forces can alter an object's moment of inertia, but in such cases, angular speed adjusts to maintain constant angular momentum. Therefore, while torque is essential for changing angular momentum, internal adjustments can occur without external torque. The discussion emphasizes the fundamental role of torque in angular motion dynamics.
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is torque required to change angular momentum?
 
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unless Newton's first law of motion doesn't hold as far as advanced physics is concerned I'm going to have to go with yes
 
Yes if one considers the N1 analogy

\tau = I \alpha

which implies if the torque is zero that the angular acceleration will also be zero giving no change in angular speed.

One can object and say - what about internal forces changing the moment of inertia of an object? In such instances it is found that the angular speed adjusts to keep the angular momentum of the object constant.
 

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