Question

A large number of particles are placed around the origin, each at a distance $R$ from the origin. The distance of the centre of mass of the system from the origin is:

• A. $=R$
• B. $\ge R$
• C. $>R$
• D. $\le R$

Answer 1

The correct option is D $\le R$

Here is says a larger number of particles are placed at distance R from the origin but it does not explain anything about the distance between the particle.

So let us take all particle together at R, so the center of moment will be at R.

Now let us separate all particles so that they all are in circle and at a distance R from the origin. In that case the center of moment lies on the origin.

Only option D $\le R$ satisfies both the conditions