This is just a very simple conceptual question. Say that someone is going down an escalator at a constant velocity. They are losing GPE, but not gaining any KE. So where is this potential energy going? Same with going up, they're gaining GPE, but not losing any KE. On a similar note, say that a crane is lifting a box upwards with a constant force, but now the box is accelerating upwards. The box is gaining GPE as well as gaining KE. Where is this energy coming from? What is losing energy accordingly? Thanks!