Question

In one dimensional motion a particle with zero speed at an instant may have non zero acceleration at that instant . Is this statement true ? If yes then specify the reason . Can a body subjected to a uniform acceleration always move in a straight line

Answer 1

This statement is false in the situation when acceleration is positive and velocity is negative at the instant time taken as origin. Then, for all the time before velocity becomes zero, there is slowing down of the particle. Such a case happens when a particle is projected upwards.