Test Preparation on Physics - Work, Energy, and Power
1.
A lorry and a car, moving with the same KE are brought to rest by applying the same retarding force then:
2.
A gas expands from 5 litre to 205 litre at a constantpressure 50 N/m2. The work done is:
W = PdV = 50 (205 - 5) = 10000 J
3.
A flywheel of mass 60 kg, radius 40 cm is revolving300 revolutions per min. Its kinetic energy will be :
4.
A constant force of 5 N is applied on a block of mass 20kg for a distance of 2.0 m, the kinetic energy acquired by the block is:
5.
Under the action of a force, a 2 kg body moves such thatf3its position x as function of time t is given by x = —t3/3where x is in metre and t is in sec, the work done by the force in first two sec is :