A 300 kg boulder is dragged 8 m across level ground

Question

with a chain that makes an angle of 37° with the
horizontal. If the applied force on the chain is 800 N
and there is a coefficient of friction of 0.20, find (a)
the work done by the applied force, (b) the force of
friction, (c) the work done by the force of friction,
(d) and the net work done by all forces.

im confused its been hours. please help!

Answer 1

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Answer 2

pulling work=800*cos37*8 Joules
force friction: (mg-800sin37)mu
friction work:(mg-800sin37)mu*8
net work. The pulling did work on friction and the movement
net work=pulling work-friction work

and the net work will equal the change of KEnergy of the boulder Notice above how pulling an an upwards angle reduces friction (have you ever moved a piano)

Answer 3

thanks