Calculating Braking Force for a 3000 lb Car

AI Thread Summary
To calculate the braking force required to stop a 3000 lb car from 40 mph to 0 in 1.5 seconds, the relevant equations include F=ma and the kinematic equation V=V_initial + a*t. The acceleration can be determined using the change in velocity divided by time, leading to a force calculation based on mass and acceleration. Understanding hydraulic systems is essential for determining the force exerted on the brake pedal, which involves the ratio of cylinder sizes. The discussion highlights a need for foundational knowledge in physics and hydraulics to solve the problem effectively.
NYCHE89
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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

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