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The question:

Skid is driving his car at 80 mi/hr. While reading the Springfield Reivedw of Books, he looks up and notices he is about to crash into a wall. When he is 100 m from the wall, he puts on the brakes. If Skid does not lock his brakes, calculate the coefficient of friction he needs so that he stops just before he hits the wall. What type of friction does he use?

My work:

I know that this involves kinetic friction. I thought I should calculate acceleration so that I can use the force equation.

I used the V^2 = V0^2 + 2a*delta X

I got an acceleration of 0.8. In order to use the SumFx = m*a equation, don't I need a mass so that I can somehow solve for the kinetic friction?

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# Homework Help: Calculate Friction

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