Question

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 (mass of particle is $1\, kg$ )?

• A. $-12 \hat{k} \,kg \,m ^{2} / s$
• B. $-24 \hat{k}\,kg \,m ^{2} / s$
• C. $-32 \hat{k} \,kg \,m ^{2} / s$
• D. $-36 \hat{k} \,kg \,m ^{2} / s$

Answer 1

Answer: (B)

$L =m v r_{\perp}$
$=(1)(3)(8)$
$=24(-\hat{k}) kgm ^{2} / s$