Work-Energy Method: Solving Doubled Initial Speed of Car

[Heat]

[SOLVED] Work-Energy Method

Homework Statement

A car is stopped by a constant friction force that is independent of the car's speed. By what factor is the stopping distance changed if the car's initial speed is doubled? (Solve using work-energy methods.)

Homework Equations

Wtotal = delta K

The Attempt at a Solution

From what the problem is stating, is that friction force, is separate from car's speed.
''if the car's initial speed is doubled?''
K1 = 1/2(m)(2v)^2

I know the answer is 4, but I don't comprehend, what is the car's initial speed is tripled, would it be 6?

 

[Doc Al]

How does stopping distance relate to kinetic energy?

 

[Heat]

well if the velocity is higher, then it would be harder to stop at a shorter distance than a long one.

 

[Doc Al]

I'm looking for a precise answer. What factors affect stopping distance? Give an equation.

 

[Heat]

well

W = F*s

s being distance

and work total = k2-k1

so, k2-k1 = F*s