Answer:
(a) 1503.6 J
Step-by-step explanation:
Weight of crate, mg = 1080 N
Applied force, F = 345 N
d = 14 m
μ = 0.22
(a)
Work done by the applied force, W1 = Appled force x distance
W1 = F x d = 345 x 14 = 4830 J
Work done by the friction force, W2 = Friction force x distance
W2 = μ x mg x d = 0.22 x 1080 x 14 = 3326.4 J
This work is negative as the direction of friction force and the distance is opposite to each other.
So, the work done by the worker on the crate is
W = W1 - W2 = 4830 - 3326.4 = 1503.6 J