AB and CD tow uniform and identical bars of mass 10kg each, as shown. The hinges at A and B are frictionless. The assembly is released from rest and motion occurs in the vertical plane. At the instant that the hinge B passes the point B, the angle between the two bars will be

Match 4 correct pairs between List $$I$$ and List $$II$$. No credit will be given for partially correct matching

List $$I$$
(a) Collision of particles
(b) Stability
(C) Satellite motion
(D) Spinning top

List $$II$$
(1) Euler’s equation of motion
(2) Minimum kinetic energy
(3) Minimum potential energy
(4) Impulse-momentum principle
(5) Conservation of moment of momentum

A rod of length 1m is sliding in a corner as shown in. At an instant when the rod makes an angle of 60 degrees with the horizontal plane, the velocity of point A on the rod is 1m/s. The angular velocity of the rod at this instant is

A ball A of mass m falls under gravity from a height h and strikes another ball B of mass m which supported at rest on a spring of stiffness k. Assume perfectly elastic impact. Immediately after the impact