AC and DC Generators
The voltage is maximum when the coil is horizontal, since the coil cuts the field at a maximum rate, and minimum when the coil is vertical.
If the ends of the coil are allowed to change contacts with every half turn, then the direction of the voltage in the coil changes as the ends of the wires change contacts, and the coil continues to flow in the same direction. This is done by using brushes and a slip ring. Connecting the generator to an external circuit allows a current to flow.
The size of the induced voltage can be increased by
1. Rotating the coil faster.
2. Using a stronger magnet.
3. Using a coil with more turns.
4. Increasing the area of the coil