- #1

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## Homework Statement

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You are traveling at a constant speed

**vM**, and there is a car in front of you traveling with a speed

**vA**. You notice that

**vM>vA**, so you start slowing down with a constant acceleration a when the distance between you and the other car is

**x**. What relationship between

**a and x**determines whether or not you run into the car in front of you?

## Homework Equations

x = v0*t - 1/2*a*t^2

## The Attempt at a Solution

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After a time t, the distance between the cars must be something larger than x if they don't want to crash, so:

vM*t-1/2*a*t^2 - vA*t > x

t(vM-1/2*a*t-vA)>x

(vM-vA-1/2*a*t)>x/t

What should be the next step after this?