- #1

EMdrive

## Homework Statement

I'm trying to digest the concept of change in potential energy being set equal to a change in kinetic energy. Does this relationship always hold? Please see below for more details.

## Homework Equations

PE = mgh

KE = .5mv^2

W = ΔKE = -ΔPE

W = f*d

## The Attempt at a Solution

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Lets say I have a block that is being pushed up an incline at constant velocity by a force F for a distance d. Because the velocity is constant, it follows that the net force on the object is 0, and therefore the total work done on the object should also be 0. This is further explained by the W = ΔKE equation in which the final and initial kinetic energies are the same, resulting in a work of 0 J. However, what baffles me is that while kinetic energy is clearly not changing, the potential energy is (height of the object is increasing). So the relationship W = ΔKE = -ΔPE does not hold because change in potential energy is some non-zero value... Can someone explain?