Question

A man displaces a block by 5m on a rough surface (u=1/2) by applying a force
50N acting at 37° to the horizontal. The work done by the applied force is
1) 200 J
2) 100 J
3) 150 J
4) 50 J​

Answer 1

The work done by the applied force is 200 J

Answer 2

Given:

A man displaces a block by 5m on a rough surface (u=1/2) by applying a force

50N acting at 37° to the horizontal.

To Find:

The work done by the applied force is?  

Solution:

it is given that - a man displaces a block by 5m on a rough surface (u=1/2) by applying a force  50N acting at 37° to the horizontal.

it means; F = 50 N,

θ = 37 degree,

displacement, d = 5m

here, force acting on a block at an angle θ.

therefore,

work done, $W=\vec F.d= Fcos\theta \ d$

$W = 50 \times cos\dfrac{37\pi}{180}\times5\\\\=50\times\dfrac{4}{5}\times5\\\\=200J$

Hence, option (1) is correct.