Question

A truck driver slams on the brakes and skids to a stop through a displacement of delta x.
(a) IF the truck has twice the mass, by what factor does the stopping distance change?
1) 0.25
or
2) 1
or
3) 4

(b) If the initial velocity of the truck were halved, by what factor would the stopping distance change?
1) 2
or
2) none of these
or
3) 4
or
4) 0.25
or
5) 1

Answer 1

(a) The answer is (2)(a factor of 1). The stopping distance does not change. That is because both the kinetic energy and the friction force double.

(b) 4) 0.25