Question

Stopping distance of a moving vehicle is directly proportional to
A. square of the initial velocity
B. square of the initial acceleration
C. the initial velocity
D. the initial acceleration

Answer 1

Correct Answer - A
Let `d_s` is the distance travelled by the vehicle before it stops.
here, final velocity v = 0, initial velocity = u, S = `d_s`
Using equation of motion
`v^(2) = u^(2) + 2aS`
`therefore` `(0)^(2) = u^(2) + 2ad_s`, `d_s = -u^(2)/2a` or `d_s propto u^(2)`