NEETPhysicsWork, Power and Energy
Consider the following statements A and B identify the correct answer given below : (A) A body initially at rest is acted upon by a constant force. The rate of change of its kinetic energy varies linearly with time (B) When a body is at rest, it must be in equilibrium.
Options
- AA and B are correct
- BA and B are wrong
- CA is correct and B is wrong
- DA is wrong and B is correct
Correct answer
C. A is correct and B is wrong
Step-by-step solution
KE = 1 2 m v^2= 1 2 m(a t)^2= 1 2 m a^2 t^2 Rate of change of KE, d K d t = d d t ( 1 2 m a^2 t^2 )=m a^2 t d K d t t So, statement A is correct. When the body is at rest, then it may be or may not be in equilibrium, so statement B is wrong.