Q20. A neutron of mass 1.67 x 10-27 kg is moving with a speed of 7 x 105 ms-1. Calculate
(i) The kinetic energy and (ii) the average force it will expert in entering a body to a depth of 0.01 cm.
Q21. A bullet of mass 20 g strikes a target with a velocity of 150 ms-1 and brought to rest after piercing 10 cm into it. Calculate the average force of resistance offered by the target.
