Two particles of mass 5 kg and 10 kg respectively are attached to the two ends of a rigid rod of length 1 m with negligible mass.
The centre of mass of the system from the 5 kg particle is nearly at a distance of :

Body A of mass 4m moving with speed u collides with another body B of mass 2 m, at rest. The collision is head on and elastic in nature. After the collision the fraction of energy lost by the colliding body A is :

A moving block having mass m, collides with another stationary block having mass 4m. The lighter block comes to rest after collision. When the initial velocity of the lighter block is v, then the value of coefficient of restitution (e) will be

Which of the following statements are correct ?

(1)   Centre of mass of a body always coincides with the centre of gravity of the body.

(2)   Centre of mass of a body is the point at which the total gravitational torque on the body is zero.

(3)   A couple on a body produces both translational and rotational motion in a body

(4)   Mechanical advantage greater than one means that small effort can be used to lift a large load.