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

A policeman sitting on a side of the road sees a speeder drive by him at 40 m/s. At the same time the speeder passing the policeman 2 things happen:

1. the policeman steps on the gas and begins to accelerate fowards at a rate of 2.5 m/s^2 until he reaches 35m/s

2. the speeder hits the breaks and begins to slow down at a rate of 4 m/s^2 untill he reaches the speed limit of 25m/s

A) How long will it take for the cop to catch the speeder?

B) How far will the policeman have to travel before he reaches the speeder

2. Relevant equations

Vf=Vi+at

x=Vi(t)+(.5)at^2

Vf^2=Vi^2+2ax

3. The attempt at a solution

I tried to solve it by setting the distance that the speeder goes equal to that of the cop and just plugging in initial velocity, acceleration, and time for both, but I did not get the right answer

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# Homework Help: Challenging police car question

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