Question

If net external force acting on the system of particles is zero , which of the following quantities remains conserved

Answer 1

Answer:

mass

I guess this will help

Answer 2

Answer:

If the net external force acting on the system of particles is zero, then the momentum of centre of mass remains conserved.

Explanation:

When the net external force on the particle is zero, then we write it as;

        $Fext = \frac{dPcm}{dt}$

        $0 = \frac{dPcm}{dt}$

       $dPcm = conserved$

where, Fext = Net External Force

           Pcm = momentum of centre of mass

So, we conclude that Pcm remains conserved when net external force is zero.

Hope it helps! ;-))