Calculating Braking Force for a 3000 lb Car

[NYCHE89]

Homework Statement

How much pressure must be exerted by the braking system of a car weighing 3000 lb, if you want to stop it from 40 mph to 0 in 1.5 seconds? Assume the total braking surface of the four wheels is 96 in^2. How much force must be exerted by your foot on the brake pedal in the absence of a vacuum assist, if the brake cylinder diameter is 3/4 inch?

Homework Equations

Am I supposed to know something about cars to answer this? I don't understand how to even start this problem.

The Attempt at a Solution

 

[mgb_phys]

What equation link force, mass and accelration?
What do you know about the ratio of cylinders in hyraulics?

 

[NYCHE89]

so I can use F=ma and V= V_initial + a*t by rearranging and coming up with
F=(m*Delta V)/t ?

As to your second question, I haven't learned anything about the ratio of cylinders or hydraulics. What is the ratio?

 

[mgb_phys]

As to your second question, I haven't learned anything about the ratio of cylinders or hydraulics. What is the ratio?

http://en.wikipedia.org/wiki/File:Hydraulic_Force_Torque_275px.png