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

A 1.47kg particle moves in the xy plane with a velocity ofv= (4.59i - 3.28j)m/s. Determine the magnitude of the particle's angular momentum when its position vector isr= (1.35i + 2.57j)m.

2. Relevant equations

p = mv

L = r x p (the x is supposed to be a cross product and not a variable)

L = r x mv

3. The attempt at a solution

First I scaled the velocity vector:v= (4.59i - 3.28j)m/s by the mass, 1.47 kg, to get a new momentum vector (6.75i - 4.82j)kg*m/s.

Then I took the cross product of thervector with the new momentum vector:

(1.35i + 2.57j)m x (6.75i - 4.82j)kg*m/s (I let a=1.35, b=2.57, c=0, d=6.75, e=-4.82, and f=0, the got the k vector cross product by doing k=ae-bd)

The answer I got was -23.9 kg*m^2/s, which wasn't right.

What did I do wrong? Am I even anywhere near the correct solution/answer?

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# Homework Help: Angular momentum cross product - Please help!

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