Question

100m
F=120N,
2. (i) Find work done by force F on A during 100 m displacement,
(ii) Find work done by force F on B during 100 m displacement,
(iii) Find work done by normal reaction on B and A during the
given displacement, (iv) Find out the kinetic energy of block
A & B finally,
20kg 710kg
А​

Answer 1

Given:

Displacement of the system = 100m

F = 120 N

To Find:

Joule

Solution:

The body experiences no displacement in relation to A.

Work Done = F×S

                   = 0

weight on B = 710 × 100 × COS0°

                    = 71000J

Weight on A = 20 × 100 × cos180°

                     = 2000J