Alternator output on a graph
The output of a generator can be represented on an induced current鈥搕ime graph which is shown below.
It shows four different positions of the coil of the generator, and the corresponding induced current.
A - The coil is at 0掳. The coil is moving parallel to the direction of the magnetic field, so no current is induced.
B - The coil is at 90掳. The coil is moving at 90掳 to the direction of the magnetic field, so the induced current is at its maximum.
C - The coil is at 180掳. The coil is moving parallel to the direction of the magnetic field, so no current is induced.
D - The coil is at 270掳. The coil is moving at 90掳 to the direction of the magnetic field, so the induced potential difference is at its maximum. Here, the induced current is in the opposite direction to what it was at B.
E - The coil is at 360掳, ie it is back at its starting point, having done a full rotation. The coil is moving parallel to the direction of the magnetic field, so no current is induced.