If the resultant of all external forces is zero, then velocity of centre of mass will be

Statement 1: Two spheres undergo a perfectly elastic collision. The kinetic energy of system of both spheres is always constant. [There is no external force on system of both spheres]. Statement 2: If net external force on a system is zero, the velocity of centre of mass remains constant.

Statement 1: Two spheres undergo a perfectly elastic collision. The kinetic energy of system of both spheres is always constant. [There is no external force on system of both spheres]. Statement 2: If net external force on a system is zero, the velocity of centre of mass remains constant.

According to the principle of conservation of linear momentum, if the external force acting on the system is zero, the linear momentum of the system will remain conserved. It means if the centre of mass of a system is initially at rest, it will remain, at rest in the absence of external force, that is, the displacement of centre of mass will be zero. Two blocks of masses 'm' and '2m' are placed as shown in Fig. There is no friction anywhere. A spring of force constant k is attached to the bigger block. Mass 'm' is kept in touch with the spring but not attached to it. 'A' and 'B' are two supports attached to '2m' . Now m is moved towards left so that spring is compressed by distance 'x' and then the system is released from rest. Find the relative velocity of the blocks after 'm' leaves contact with the spring.

Show that in the absence of any external force, the velocity of the centre of mass remains constant.

The resultant force of unbalanced forces is zero.

If the resultant external force on a system is zero, then the total…………of system remains constant.