Question

A factory worker pushes a package along a broken conveyer belt from (-4,0) to (4,0) with a 50-N force at a 30 degree angle to the conveyor belt. How much mechanical work is done if the units of the conveyor belt are metres?

Answer 1

W= F*displacement*cos(angle of displacement)

W= 50N * 8m * cos(30)
W= 50N * 8m * 0.86603
W=346.4 J

Answer 2

so the 8 if from -4 to 4

Answer 3

yea, because you cant have a negative distance (displacement is simply a distance). They assigned -4 and 4 to throw you off. They are just using a Cartesian coordinate system and didn't set their reference point to 0

Answer 4

okay, thank you !

Answer 5

no problem