First slide

Work

Question

A particle of mass 0.1 kg is subjected to a force which varies with distance as shown in fig. If it starts its journey from rest at $x = 0$ , its velocity at $x = 12 m$ is

Moderate

A

0 m/s
B

$20 \sqrt{2} m / s$
C

$20 \sqrt{3} m / s$
D

$40 m / s$

Solution

Area between curve and displacement axis
= $\frac{1}{2} \times (12 + 4) \times 10$ = 80 J
In this time body acquire kinetic energy = $\frac{1}{2} {mv}^{2}$
by the law of conservation of energy
$\frac{1}{2} {mv}^{2} = 80 J$
$\Rightarrow \frac{1}{2} \times 0 .1 \times v^{2} = 80$
$\Rightarrow$ v² = 1600
$\Rightarrow$ v = 40 m/s

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App