- #1

lauriecherie

- 44

- 0

## Homework Statement

On a dry road, a car with good tires may be able to brake with a constant deceleration of 4.06 m/s2.

(a) How long does such a car, initially traveling at 23.6 m/s, take to stop?

__5.813__s

**This answer is correct.**

(b) How far does it travel in this time?

I've tried 59.47 m and 137.1868 but Webassign says both are incorrect. I have no clue as to what I am doing wrong.

## Homework Equations

x(t)= initial position + final velocity * time

v(t)= (acceleration * time) + initial velocity

x(t)= .5 * (acceleration * (time^2)) + (initial velocity * time) + inital position

x= initial position * (average velocity * time)

average velocity= (final velocity - initial velocity) / (2)

(final velocity^2) - (initial velocity^2) = 2 * acceleration * change in position

## The Attempt at a Solution

I got 59.47 meters by pluging in part a, 5.813 seconds, into the position function.

Then I tried 137.19 meters after figuring that in 5.813 seconds at 23.6 m/s (I multiplied the two) it could travel 137.19.

Any ideas on what I am doing wrong?