# Question #ed216

Aug 18, 2016

$3850.4 N$, rounded to one decimal place.

#### Explanation:

Step 1. We need to calculate the deceleration $a$ required to bring the car to halt from a speed of $u = 13.5 m {s}^{-} 1$ in the specified distance $s$.
We use the kinematic equation
${v}^{2} - {u}^{2} = 2 a s$

Inserting given quantities we obtain
${0}^{2} - {13.5}^{2} = 2 \times a \times 37.7$
Solving for $a$, we get
$a = - {13.5}^{2} / \left(2 \times 37.7\right) m {s}^{-} 2$

Step 2. To calculate the magnitude of required force $F$ we use the relationship obtained from Newton's second law of motion.
$F = m a$
$F = 1593 \times {13.5}^{2} / \left(2 \times 37.7\right)$
$\implies F = 3850.4 N ,$ rounded to one decimal place.