# Angular momentum newbie question

If pulling the string down, and shortening the radius to r/2, increases the tangential velocity of the object, I suppose releasing the string, so the radius increases to 2r, will diminish its tangential velocity of the object. Is this correct? How does the velocity diminish? Thank you.

Make a drawing as the one I gave. Release the string. The object continues in a tangential straight trajectory. Wait until its distance to the center is 2R. Look at the speed: decompose it in a component parallel to the circle of radius 2R and a radial component. Hold again the string. The radial component is annulled and only rests the tangential component which is smaller than the original one.
Is it clear?

Doc Al
Mentor
I suspect that when Peter57 referred to "releasing" the string he meant easing up the tension so that the radius increases. I don't think he meant "release" in the sense of letting go of the string entirely.

I suspect that when Peter57 referred to "releasing" the string he meant easing up the tension so that the radius increases. I don't think he meant "release" in the sense of letting go of the string entirely.

I do not think that it matters. What Peter57 want is understand how the things happen. I hope that what I explained to him will help. I'm sure that, once he has understood what happen if he releases the string completely and then immobilize it when the object has attaint the 2R, he will have understood what happens if he lets go the string slowly.

Assuming your x is the new value of w, we would have x = 2w.

My postings are being suppressed; we are back in the dark ages.

Doc Al
Mentor
My postings are being suppressed; we are back in the dark ages.
The only posts that were "suppressed" are those where you discuss your personal redefinition of angular momentum. (See the section about overly speculative postings in our https://www.physicsforums.com/showthread.php?t=5374".)

If you have questions about or wish to discuss mainstream physics--have at it!

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Hootenanny
Staff Emeritus