# Lifting electromagnet & Induced EMF

An electromagnet is lifting/pulling large pieces of iron, from a distance $r$. Is there an induced EMF in the coils of the electromagnet due to the change in flux?

Another configuration would be the piece of iron is rotating around the electromagnet is there still EMF induced?

I'm confused because if a ferromagnet is introduced to a magnetic field, there is a change if flux, however, is the magnetic field produced by the ferromagnet = to the external magnetic field? Also are there large voltages induced?

## 1 Answer

Any time there's a change in the flux in the coil for whatever reason there will be an induced EMF in the coils.

• In this case, how is there change? Increase in flux or... & That change is equal to -N delta(BA)/delta (t)? – Pupil Mar 1 '14 at 0:51