Question

Q 154 Two forces of 5 N and 15 N are working on a body in opposite direction. If body displaced by 5 m in direction of net force ,what will be the work done by net force. (a) 50j (b) -50j (c) 100j (d) 120j​

Answer 1

Given:

Two forces of 5 N and 15 N are working on a body in opposite direction. Displacement = 5m.

To find:

Work done ?

Calculation:

Net force will be :

$F = 15 - 5 = 10 \: N$

Now, work done will be :

$W = F \times d \times \cos( \theta)$

$\implies \: W = 10 \times 5 \times \cos( {0}^{ \circ} )$

$\implies \: W = 10 \times 5 \times 1$

$\implies \: W = 50 \: joule$

So, work done is 50 Joule.

Answer 2

Given:

Two forces of 5 N and 15 N are working on a body in opposite direction. Displacement = 5m.

To find:

Work done ?

Calculation:

• Net force will be :

$f = 15 - 5 = 10n$

Now, work done will be :

$w = f \times d \times \cos(o)$

$= > w = 10 \times 5 \times \cos(0°)$

$= > w = 10 \times 5 \times 1$

$= > w = 50 \: joule$

So, work done is 50 Joule