# A small mass m is attached to a massless string whose other end is fixed at P as shown in the figure…

Q: 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 O and constant angular speed ω. If the angular momentum of the system, calculated about O and P are denoted by LO and LP respectively, then

(a)Lo and LP do not vary with time

(b)Lo varies with time while LP remains constant

(c)Lo remains constant while LP varies with time

(d)Lo and LP both vary with time

Ans: (c)

SOl: $\large \vec{L} = m(\vec{r}\times \vec{v})$