If a car traveling at 60 km/h will skid 20 m when you brake, how far will it skid when traveling 120 km/h?

Question

Explain.
Plzzz Help

Answer 1

Hey Champ. This is a Kinetic Energy (KE) question.

The equation for KE is:

KE = 1/2(mass)(velocity)^2

So, if you double the velocity (which is squared) you increase the KE four fold!

So, the stopping distance at double the speed would be a product of the car having four times the KE. Thus, the stopping distance will be four times greater.

Hope this helps you. Best wishes and good luck.

Answer 2

The frictional force is F = f*mg (f is the coefficient of friction) and the work made is W = - F*d = - f m g d .
Then W = 0 - (1/2) m V^2
and : - f m g d = - (1/2) m V^2.
d is proportional to the square of the speed . So doubling the speed quadruplicate the skid: 80 m