Calculating Braking Time for 800 kg Car

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    Braking Car Time
AI Thread Summary
To calculate the braking time for an 800 kg car with a braking force of 4.4 kN, the relevant equations involve Newton's second law, which relates force, mass, and acceleration. The acceleration can be determined by dividing the braking force by the mass of the car. Once acceleration is known, the time to stop from an initial speed of 34 m/s can be calculated using the formula that relates acceleration, initial speed, and time. The discussion emphasizes the need to apply these fundamental physics equations correctly to solve the problem. Understanding these concepts is crucial for accurately determining braking time.
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so lost! help!

Homework Statement



The brakes of an 800-kg car exert a force of 4.4kN. (a) how long will the brake take to slow the car to a stop from an initial speed of 34m/s

Homework Equations





The Attempt at a Solution

 
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Hi there lindzpooh and welcome to the forums,

Do you know a (quite famous) equation that links force, mass and acceleration?
 
i know mass is E0=Mc2
acceleration= change in speed/time interval
 
Yes, your second one will be useful, but you need another one as well, Newton thought of it I believe...
 
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