# A car driving at 41m/s hits the brakes and comes to a stop in 4.8 seconds. What was the car's acceleration during this stop?

Aug 22, 2015

$a = - 8.54 \text{ } m . {s}^{-} 2$

#### Explanation:

The acceleration is the rate of change of velocity.

If $u$ = initial velocity

$v$ = final velocity

$t$ = time:

$a$ = accelaration

Then:

$a = \frac{u - v}{t}$

$a = \frac{0 - 41}{4.8} = - 8.54 \text{ } m . {s}^{-} 2$

The minus sign signifies that the car is decelerating.