# Question #51236

Oct 19, 2016

(a)

#### Explanation:

We are required to find out the force.

We know that
Force $F = m a$.
Mass $m$ is given.
What we need to find is acceleration $a$ from the given data.

Kinematic equation connecting given quantities is
$s = u t + \frac{1}{2} a {t}^{2}$
Inserting given values we get
$s = 0 \times t + \frac{1}{2} a {t}^{2}$
$\implies \frac{1}{2} a {t}^{2} = s$
Solving for $a$
$a = \frac{2 s}{t} ^ 2$
$\therefore$ Force $F = m \times \frac{2 s}{t} ^ 2$
$F = \frac{2 m s}{t} ^ 2 N$