Two balls of clay approach each other. Calculate the total angular momentum relative to the origin

Question

The figure: http://session.masteringphysics.com/problemAsset/1070558/3/12.P82.jpg

- Calculate the total angular momentum relative to the origin at this instant.

- Calculate the total angular momentum an instant before they collide.

- Calculate the total angular momentum an instant after the collision.

- Express your answer using two significant figures and show all work from setup of formulas (and the reason for such a setup in the formulas) to the actual answer with a minimal of skipping of steps.

Answer 1

L = ΣP*R

R = 1.0

ΣP = 15*2 - 25*2 = -20 g∙m/s

L = (-20)*1.0 = -20 g∙m²/s where CW rotation is +

Since ΣP and R do not change at any time before, during or after the collision, L remains constant with time.

Answer 2

L = 0.02 kg∙m²/s

The answer is going to be the same for all three answers since angular momentum is conserved in this problem.