A child walks towards a fixed plane mirror at a speed of 5 km h−1. The velocity of the image with respect to the mirror is -
Calculate the recoil velocity of a gun having mass equal to 5 kg, if a bullet of 25 g acquires the velocity of 500 ms−1 after firing from the gun.
Two putty balls of equal masses moving with equal velocity in mutually perpendicular directions, stick together after collision. If the balls were initially moving with a velocity of 45√2 ms−1 each, the velocity of their combined mass after collision is