Question

Two particles $A$ and $B$ are moving as shown in the figure. Their total angular momentum about the point $O$ is

• A. 9.8 kg $m^2/s$
• B. Zero
• C. 52.7 kg $m^2/s$
• D. 37.9 kg $m^2/s$

Answer 1

Answer: (A)

9.8 kg $m^2/s$

Answer 2

Total angular momentum about $O$ is given as,
$L = L _{1}+ L _{2}=m_{1} v_{1} r_{1}+m_{2} v_{2} r_{2}$
$=-6.5 \times 2.2 \times 1.5+3.1 \times 3.6 \times 2.8$
$=-21.45+31.248=9.8\, kgm ^{2} / s$