(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The brakes of a 1452 kg car bring it to a stop from a speed of 17.2 m/s in a distance of 100 m. If the car originally stops in 6.2 s (100 m), what power is developed by the brakes?

2. Relevant equations

W = FF Δs

W = ½ m· v^2

P = W/t

P = F * v

3. The attempt at a solution

W = 1/2 * m * v^2

W = 1/2 * 1452 kg * 6.2 s ^2

W = 214779.84 J

P = W/t

P = 214779.84 J/6.2 s

P = 4501.2 W

I know that this isn't correct because it is a multiple choice study guide. The options are the following:

a. 230 kW

b. 34.7 kW

c. 23.4 kW

d. 2.15 kW

It is the only problem I can't solve, and I'd like to know how to! Thank you.

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# Homework Help: What is the power?

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