(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

a 1.5 kg pendulum bob swings in a vertical circle at the end of a 2m long string with negligible weight. If the bob is dropped from a height in which the string is horizontal and taut, what is the angular momentum at the bob's lowest point (in kgm/s^2)?

a 40

b 10

c 30

d 20

e 50

2. Relevant equations

L=Iw

L=mrv

L(initial)=L(final)

3. The attempt at a solution

I tried using the formula v^{2}=v_{o}^{2}+2aΔy to solve for linear velocity first. It would be v= sqrt(2*9.8m/s/s*2m) because it falls the length of the string to reach the horizontal correct? From there, I calculated v to be 6.26m/s, and then subbed that into L=mrv for a final answer of 18.78kgm^{2}/s, but its a bit off the possible choices and I'm skeptical of my work.

Any help would be greatly appreciated!

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# Homework Help: Angular Momentum (pendulum) Help

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