# ques) A point mass starts moving in a straight line with constant acceleration. After time to the acc changes its sign, remaining the same in magnitude. Dtermine the time t from the beginning of motion in which the point mass returns to its initial problems.

Arun Kumar IIT Delhi
8 years ago
initial position you mean.

Hi Keerthi,
$\\ x_1=1/2a*t_0^2 \\v=at_0 \\v=0\,at\,t=t_0 \\x_2=v^2/2a=1/2(at_0^2) \\now\,(1/2)at^2=at_0^2 \\=>t=t_0\sqrt2\\ T_{total}=2t_0+\sqrt2t_0$

Thanks & Regards

Arun Kumar

IIT Delhi