The position of the magnet with respect to the door (for the force produced by the magnet) or the ground (for the force of gravity) must change for energy to be lost or gained.
(the force; produced; by the magnet) (The position of the magnet with respect to the door (for the force produced by the magnet) or the ground (for the force of gravity; must change; for energy to be lost or gained) (energy; to be lost; ) (energy; to gained; )
the force The position of the magnet with respect to the door (for the force produced by the magnet) or the ground (for the force of gravity energy energy
produced must change to be lost to gained
by the magnet
for energy to be lost or gained