Question

A parachutist after bailing out falls for $10$ $s$ without friction. When the parachute opens he descends with an acceleration of $2m/s^2$ against his direction and reached the ground with $4m/s$. The total time of journey is $(g=10m/s^2)$:

• A. 10 s
• B. 48 s
• C. 38 s
• D. 58 s

Answer 1

The correct option is D 58 s

$v=g{t}_1[t_1=10sec]$
$v=10\times 10=100$ m/s

We know that, $v=u+at$
$\Rightarrow u=100-2t_2$; $u=4m/s;t=t_2$
$\Rightarrow [t_2=48sec]$
Total time $=10+48=58sec$