A particle of mass m is projected with velocity v making an angle of 45^o with the horizontal. When the particle lands on the level ground the magnitude of the change in its momentum will be :

A 0.5 kg ball moving with a speed of 12 m/s strikes a hand wall at an angle of 30^o with the wall. It is reflected with the same speed at the same angle. If the ball is in contact with the wall for 0.25 seconds, the average force acting on the wall is :

A bomb of mass 30 kg at rest explodes into two pieces of masses 18 kg and 12 kg. The velocity of 18 kg mass is 6 m s^$$-$$1. The kinetic energy of the other mass is :

Consider a system of two particles having masses m₁ and m₂. If the particle of mass m₁ is pushed towards the mass centre of particles through a distance d. by what distance would be particle of mass m₂ move so as to keep the mass centre of particles at the original position?