Question

A body of mass $100\text{grams}$ is allowed to fall freely under gravity. Find its momentum after $10$ seconds (in $\text{N- s}$)

• A. $10$
• B. $20$
• C. $30$
• D. $40$

Answer 1

The correct option is A $10$

Let the initial velocity be $u$,
and velocity after $10$ seconds be $v$,

Taking downward as positive and relating $u$ and $v$

$v=u+at$
$v=0+10t=100m/s$ .
Momentum $p=m\times v$
Momentum $p=0.1\times 100=10N-s$