A car goes through a turn of radius $r = 50$ m at a speed of $v = 72$ km/h. Find the centripetal acceleration of the car.
Convert the speed to metres per second:
$$v = \frac{72}{3.6} = 20 \text{ m/s}$$
$$a = \frac{v^2}{r} = \frac{20^2}{50} = \frac{400}{50} = 8 \text{ m/s}^2$$
$a = 8$ m/s²