Question

. A car is moving with a constant speed on

straight line

a) What is the network done by the external

force on the car?

b) State work energy theorem.

c) A bullet of mass 10g and velocity 800 m/s

is passed through a mud wall of thickness 1 m.

Its velocity reduces to 100m/s. Find the

average resistance offered by the mud wall.

Answer 1

Answer:

c)

a) If the car moves at constant speed, then there is no change in its kinetic energy. It implies that if there is no change in kinetic energy then there is no work done by the force on the body

b) The work-energy theorem states that the work done by the net force acting on a body is equal to the change produced in the kinetic energy of the body.