Relating friction with acceleration

[elimenohpee]

Homework Statement

If the coefficient of kinetic friction between tires and dry pavement is 0.80, what is the shortest distance in which you can stop a car by locking the brakes when traveling at 28.7 m/s?

Homework Equations

The problem doesn't state the mass of the car, so I'm not sure how to exactly relate kinetic friction with the acceleration.

The Attempt at a Solution

v^2 = 0 + 2a(x - 0)
v^2/2a= x

a?

 

[LowlyPion]

Mass will drop out.

What is the maximum deceleration the car will tolerate?

Won't that be when m*a = μ*m*g ?

 

[elimenohpee]

OHHHH so it doesn't even depend on mass, so I can plug a = ug, which just gave me the correct answer :)

Thanks!