# Question #f5e2e

Jul 14, 2017

I got $13.6 \frac{m}{s} ^ 2$ in opposite direction to the car motion (a deceleration).

#### Explanation:

We can use the Kinematic relationship:

${v}_{f} = {v}_{i} + a t$

with:

${v}_{f} = 0$ final velocity;
${v}_{i} = 45 \frac{m}{s}$ initial velocity;
$t = 3.3 s$ time;
$a =$acceleration.

We get:

$0 = 45 + 3.3 a$

rearranging:

$a = - \frac{45}{3.3} = - 13.6 \frac{m}{s} ^ 2$

opposite to the movement and decelerating the car.