Question

For a system of particles if ${\tau }_{\text{ext }}=0,$ then choose the correct option:

• A. $\frac{dL}{dt}=$ constant $\ne 0$
• B. $1=$ constant
• C. $L=$ Constant
• D. None of these

Answer 1

Answer: (C)

If ${\tau }_{\text{ext }}=0,$ then
$\frac{dL}{dt}=0$
$L=\text{ constant }$
If ${\tau }_{\text{ext }}$ is zero, then the total angular momentum of the system remains conserved. Conservation of angular momentum is rotational analogue of conservation of linear momentum