# Motion at constant acceleration

steve snash

## Homework Statement

In coming to a stop, a car leaves skid marks 92m long on the highway. Assuming a deceleration of 7.00m/s^2 estimate the speed of the car just before braking.

## Homework Equations

deceleration=7m/s^2, distance=92m

## The Attempt at a Solution

I found there was not enough information to solve the problem, but i had a go, assuming dividing the distance by deceleration you would get time. 92/7 =13.14 seconds

I substituted this into the equation of motion x=x0+v0t+1/2at^2
=52.99m/s. Is this right???????

NEED TO KNOW BY TOMORROW