You push your couch a distance of 3.6 m across the living room floor with a horizontal force of 198.0 N. The force of friction is 151.0 N. What is the work done by you, by the friction force, by gravity, and by the net force?

2 answers

by you: 198*distance
by friction: 151*distance
by gravity: zilch
net force= force pushing-frictionforce
W=F.d , W= (198.0N)(3.6m)cos 0, W=712.8 N.m

this is your work.

W=(151.0N)(3.6)cos 180, W=(-1)543,6N.m

this work is negative because the force of friccion is opposite a the direction of movement y therefore the angle is 180

for last the total work is the sum of the all work

PS: the work of gravity is perpendicular
a the movement therefore cos 90 = 0.
Work gravity is 0

enjoy your answer.