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The time dependence of the position of a particle of mass m = 2 is given by j ˆ t 3 i ˆ t 2 ) t ( r 2 − = G . Its angular momentum, with respect to the origin, at time t = 2 is

1. 36 k ˆ
2. – 48 k ˆ
3. – 34 ( k ˆ – i ˆ )
4. 48 ( i ˆ +s j ˆ )

Correct answer: – 48 k ˆ

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