- #1

-Dragoon-

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## Homework Statement

Andrew is driving his van to deliver groceries in Elmvale. As he travels along the highway, a fox stops on the road. Andrew is traveling at 75km/h and is 42m away from the fox when he applies his brakes. It takes him 3.4 seconds to stop.

a) How far did Andrew travel before stopping?

b) Did Andrew hit the fox? Explain your answer by including a calculation.

c) If a typical van is 4.2m in length, how many van lengths did it take Andrew to stop?

## Homework Equations

Distance = V1 (delta t) + 1/2 (a)(delta t^2)

Distance = V2 (delta t) - 1/2 (a)(delta t^2)

## The Attempt at a Solution

For part a:

So I first convert 75km/h into m/s, to get 20.8 m/s. I know distance = velocity times change in time. Therefore, delta D = 20.8m/s(3.4 seconds) = 70.8m, is this really the distance he traveled before stopping?

For part b: You see, this is why I don't think my answer for part a) is correct. If it were, it is obvious he hit the fox because he travels 70.8m before hitting the fox and he was only 42m away when he applied the breaks. Why would they ask me this question if he didn't?

For part c: By using the answer I got in part a, it would be 70.8/4.2 correct? Which gives 16.8m, which is about 17 vans?

I don't believe I am correct, as I just learned a couple more complex equations but don't exactly know how to apply them. Thanks for all the help!