Question

A small mass m is attached to a massless string whose other end is fixed at p as shown in the figure. The mass is undergoing circular motion in the x-y plane with centre at 0 and constant angular speed $\omega$. If the angular momentum of the system, calculated about o and p are denoted by $L_{o}and{L}_p$ respectively, then

• A. $L_{o}and{L}_p$ do not vary with time.
• B. $L_o$ varies with time while $L_p$ remains constant.
• C. $L_o$ remains constant while $L_p$ varies with time.
• D. $L_{o}and{L}_p$ both vary with time.

Answer 1

The correct option is C

$L_o$ remains constant while $L_p$ varies with time.

$L_o$ remains constant while $L_p$ varies with time because the direction of angular momentum keeps on changing.