I'm really confused how to chose height when calculating potential energy. If an object is right above a desk, suppose the will we take height from desk?
If we take it from a height $x$ from the desk and the level of desk is $y$ from the ground and we change the position of the object such that now the object is directly above the floor. So will the potential energy change as height changes and if so, we know that potential energy is stored energy.
Will the stored energy increase?