Hi, this one is probably easy, but I just can't wrap my head around it.(adsbygoogle = window.adsbygoogle || []).push({});

You are arguing over a cell phone while trailing an unmarked police car by 25m; both your car and the police car are traveling 110km/h (about 31m/s). You take your eye off the road for 2.0s because of the argument. At the very beginning of the 2.0s, the police car brakes at 5m/s^2

a) what is the separation between the two cars when your attention returns?

I worked it out and I got about 20m. Is this about right?

b) Suppose you take another .40s to realize the danger and begin braking. If you too brake at 5m/s^2, what is your speed when you hit the police car?

I'm not too sure how to set this one up. I'm thinking it has to be a system of equations...

after 2.4s the distance should be 19m, but how do I set up the system from there?

The equations in the chapter are the equations for motion with constant acceleration.

thanks

Matt

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# Homework Help: Constant Acceleration of police car

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