Question

A particle Moving along a straight line such that it's displacement at any time t given by s=t³-6t²+3t+4 meters. The velocity when the acceleration is zero is
1) 3 m/s
2) -12 m/s
3) 42 m/s
4) -9 m/s​

Answer 1

Answer: correct answers is - 15 m/s

Explanation:

S = t^3 - 6t^2+3t+4

Differtiation of s with respect to t gives us velocity.

Therefore, v = 2t^2-12t+3

Differtiation of v with respect to t gives us acceleration.

Therefore, a = 4t-12 =0 (a =0) given

So, t = 3 seconds.

Put t=3 s in v,

Therefore, the final answer is

V = 2*9 - 12*3 + 3 = 21 - 36 = - 15 m/s.

Hope it helps you!