Question

A body constrained to move in y-direction to a displacement of 10 units is subjected to force F= 2i+15j+6k N. Find the work done by moving in y-direction?

Answer 1

Hello!

$\vec{\sf F}$ = 2i + 15j + 6k  N

Then,

$\bf{Workdone}$ :

=  F . s = (2i + 15j + 6k) . 10j J
     
=  20 i . j + 150 j . j + 60 k . j = $\boxed{\sf 150 \:N}$

$\underline{\sf Here}$ :

• j . j = 1
•  i . j = 0
•  k . j = 0

Cheers!