A force acts on a 3.0 g particle in such a way that the position of the particle as a function of time is given by  x = 3 t – 4 t ² +  t ^3, where x is in meter and  t  in second. The work done during the first 4 s is 

If kinetic energy of a body is increased by 300% then the percentage change in momentum will be

A bullet of mass 10g leaves a rifle at an initial velocity of 1000m/s and strike the earth at the same level with a velocity of 500m/s. The work done in joule to overcome the resistance of air will be

Two equal masses m₁ and m₂ moving along the same straight line with velocities +03 m/s and -5 m/s respectively collide elastically. There velocities after the collision will be respectively

The coefficient of restitution  e for a perfectly elastic collision

An engine pumps water continuously through a hose. Water leaves the hose with a velocity v and m is the mass per unit length of water jet. What is the rate at which kinetic energy is imparted to water? 

A stone is thrown at an angle of 45^o to the horizontal with kinetic energy K. The kinetic energy at the highest point is

Two masses 1g and 9g are moving with equal kinetic energies. The ratio of the magnitudes of their respective linear momenta is

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

A child swinging  a swing. Minimum and maximum heights of swing from earth’s  surface are 0.75 m and 2m respectively. The maximum velocity of this swing is