An 80 kg pumpkin is pushed at a constant velocity along a frictionless incline (10 m high, 7 m long) How much work is done on the pumpkin in moving it up the incline?

Question

anonymous · Answer

Frictionless pushing with no acceleration means you are going up rather than down and the work done is the change in potential energy of the pumpkin from PE=0 at the bottom to PE = m g h at the top, mass x gravity x height. Since velocity remains the same no kinetic change occurred.

anonymous · Answer

The answer is supposed to be 5544 but if I do m*g*h it comes out as 7840. I'm actually not sure is 10 even is the height since (see drawing) but even if you do 80*9.8*7, it's 5488.
Also, I think no friction + constant velocity = no work only applies to level surfaces, since work is done against gravity.

anonymous · Answer

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anonymous · Answer

"10 m high" can only mean vertical distance is 10 m
"7 m long" could be the ramp length, but here must be the length along the ground, as 10 m high rules out 7 m hypotenuse

The two reasons for work: friction=not present, gravity = m g h.  Cannot see it differently.

anonymous · Answer

The question doesn't actually say those are the height and length. I just put that because I couldn't draw the diagram at the time. I was just saying that, based on the diagram, it's possible 7 is the height and 10 is the hypotenuse. Thanks for trying to help anyways.