Angular Momentum Dimensional Analysis

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k3r0
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Homework Statement


"A particle of mass m moves in a circle of radius R. Using dimensional argument,
determine the particle angular momentum."

Homework Equations


L = mvr


The Attempt at a Solution


Because L = mvr, the dimensionality would be ML2T-1. I don't know where to go from here so if someone could point me in the right direction it'd be appreciated.

Thanks!
 
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You need to take the problem backward, compared to what you wrote.

To use a "dimensional argument," you start by the units, and then figure out how to construct an equation (with parameters you know) that will have the correct units.

So start with the fact that the units of angular momentum are ML2T-1, and find a way to argue that this means that ##L = m v R##.
 
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I should add that dimensional arguments are, at best, correct up to a dimensionless constant.