Question

if the velocity of a car is halved the fc required to keeo it in a path of constant radius is multiplied/divided by?

Answer 1

I believe this is it
The centripetal force is given by
F = mv^2 / r
When v' = v/2,
F' = mv'^2/r = m(v/2)^2/r = mv^2/4r = F/4.
So the centripetal force is divided by 4.

Answer 2

It should be the 4... so the answer is 4...