Question

A man with a motorcycle driving on a straight road with a speed of 90 km / h . The mass of men along the bike of 100 kg .The officers chasing criminals from behind men using a helicopter , flying at an altitude of 500 m above the ground and at a speed of 144 km / h . The officer dropped the body of mass 400 kg ( without giving the initial speed of the helicopter ) . It turns out objects just overwrite the officer released the man .

In a system that consists of men along with the bike and the object is released attendant , find the acceleration of the center of mass and center of mass equation of motion