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The time dependence of the position of a...

The time dependence of the position of a particle of mass m = 2 is given by `vec(r) (t) = 2t hat(i) - 3 t^(2) hat(j)` Its angular momentum, with respect to the origin, at time t = 2 is :

A

`-34 (hatk - hati)`

B

`-48 hatk`

C

`36hatk`

D

`48(hati + hatj)`

Text Solution

Verified by Experts

The correct Answer is:
B
`vecL =m(vecr xx vecv)`
`vecr = 2thati - 3t^(2) hatj rArr v+ 2hati - 6hatj = 4hati -12 hatj = 2hati - 12hatj rArr vecL = -48 hatk`
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