Posted by John on .
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

Physics 
drwls,
(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