Question

11. When a force of 50 N acts on a body, the body is displaced through a distance of 3 m in a 3 m direction normal to the direction of the force. The work done by the force is (a) 150 ) (b) 1470 ) (c) Zero (d) -150 ]​

Answer 1

Given : Force = 50N

           Distance = 3m

           angle (Ф) = 90⁰

To find : work done by the force

Solution : work is said to be done when a force applied to a body causes the displacement of body. So, work is a scalar product of force and displacement.                    

                        Work done = F.S

                                           = FSCos(Ф)

                                           = 50×3×Cos90⁰

As Cos90⁰=0

                                     = 0

So, no work is said to be done , because force is acting normal to the displacement.

Therefore, option C is correct.                                    

Answer 2

Here's the answer....Hope it helps