1)

A particle of mass m is moving along the side of a square of side a, with a uniform speed v in the XY-plane as shown in the figure

332020327_stete.JPG

Which of the following statements is false for the angular momentum L about the origin?


A) L=mv2Rˆk when the particle is moving from A to B

B) L=mv(R2a)ˆk when the particle is movinf from C to D

C) L=mv(R2+a)ˆk when the particle is moving from B to C

D) L=mv2Rˆk when the particle is moving from D to A

Answer:

Option B,D

Explanation:

We can apply L=m(r × v) for different parts

   For example

if part (a) , cooredinates of  A are  (R2,R2)

there fore ,r = R2ˆi+R2ˆj   and  v=vˆi

So, subsuituting in L=m(r× v) we get,

   L=mvR2ˆR

Hence, option (a) is correct, similarly , we can check other options also