When you have a magnet moving up and down a coil. The magnet cuts the field lines. Which generates an AC current in the coil. In my exam, there was a sinusoidal curve showing the generation of AC current. When the curve crossed the x-axis, that point was labelled X. Now at that point was the magnet moving or was it stationary? and why? Be careful, the magnet isn't rotating it is going up and down the coil.