# Calculating Braking Force for a 3000 lb Car

• NYCHE89
In summary, to calculate the pressure needed for the braking system of a 3000 lb car to stop from 40 mph to 0 in 1.5 seconds, the equation F=(m*Delta V)/t can be used. The ratio of cylinders in hydraulics is used to determine the force needed to exert on the brake pedal, which is necessary to apply the calculated pressure.
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

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?

## 1. What is braking force?

Braking force is the force exerted by the brakes of a vehicle that slows or stops its motion.

## 2. How is braking force calculated?

Braking force can be calculated by multiplying the coefficient of friction between the tires and the road surface by the weight of the vehicle.

## 3. What is the coefficient of friction?

The coefficient of friction is a measure of the grip or traction between two surfaces in contact with each other.

## 4. How do I determine the coefficient of friction for a 3000 lb car?

The coefficient of friction can be determined by conducting a controlled braking test on a flat surface and measuring the stopping distance of the car at different speeds.

## 5. Are there any other factors that affect braking force?

Yes, in addition to the coefficient of friction, factors such as the condition of the brakes, tire pressure, and road conditions can also affect the braking force of a vehicle.

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