A particle starts from point (0,8) metre and moves with uniform velocity of vec{v}=3 hat{i} ,m / s .

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6.System of Particles and Rotational Motion

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A particle starts from the point $(0,8)$ metre and moves with uniform velocity of $\vec{v}=3 \hat{i} \,m / s$. What is the angular momentum of the particle after $5 \,s$ about origin is ........... $kg m ^2 / s$ (mass of particle is $1 \,kg$ )?

A

$-12 \hat{k}$

B

$-24 \hat{k}$

C

$-32 \hat{k}$

D

$-36 \hat{k}$

Solution

(b)

$L =m v r_{\perp}$

$=(1)(3)(8)$

$=24(-\hat{k}) \,kgm ^2 / s$

Standard 11

Physics

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