Where does the energy come from to move a compass needle?

The energy comes from people. This is essentially what Martin Hogbin was saying, but let me elaborate on his point. The magnetic field can indeed store energy and then deliver it back to an object. However, saying the energy to move the needle came from the field is only half of the answer. read more

The energy comes from people. This is essentially what Martin Hogbin was saying, but let me elaborate on his point. The magnetic field can indeed store energy and then deliver it back to an object. read more

The compass needle is a magnetic dipole. (close to it, okay) with it comes a vector, known as the magnetic dipole moment "mu". the energy between a magnetic dipole and a magnetic field is E~ mu * B * cos(alpha) where B is the local magnetic field value, mu is the magnetic dipole moment value and alpha is the angle between the two vectors. read more

This is because the part pointing north in a compass is a North Pole and the closest pole to us is a South Pole. Opposites attract. read more