Explain the construction and working of the alternate current generator and also draw the essential diagram.

An electric generator is a device which converts mechanical energy into electrical energy with the help of using electromagnetic induction.

CONSTRUCTION – Parts of an AC Electric Generator are:-

● Insulated Copper wire: A rectangular rotating coil of wire ABCD made of copper due to its low resistivity.

● Magnet Poles: A magnet as placed above that is the North Pole and the South Pole. The rectangular coil is placed between these magnets, so that it rotates and cuts the magnetic field. The higher the magnetic field the greater the amount of induced emf is produced.

● Split Rings: Two disjoint C-shaped rings R1 and R2 are internally attached to the Axle.. Ends of the coil are connected to R1 and R2. The inner portion of these rings are made of non-conducting material

● Axle: The split rings are placed on the axle which is made to rotate freely from an external source.

● Brushes: The outside of the split rings are connected to conducting brushes B1 and B2. B1 and B2 are kept pressed on R1 and R2.

● Galvanometer: To find the presence of current, formed due to electromagnetic induction galvanometer shows deflection. The deflection changes in it after each half rotation because of change in direction of induced emf.

WORKING – Steps:-

● The axle is rotated in the clockwise direction that is AB moves up and CD moves down. In the first half rotation.

● According to Fleming's Right-Hand rule, the induced current is setup in the coil along B1-> AB -> BC -> CD -> B2. This means that the external current flows from B2 to B1. In order to complete the circuit.

● In the second half of rotation, arm CD starts move up and AB moves down. That is in the opposite direction of the first half.

● According to Fleming's Right-Hand rule, the induced current is setup in the coil along B2-> AB -> BC -> CD -> B1. This means that the external current flows from B1 to B2.

● Thus after every half rotation of the coil, the current changes direction due to induced e.m.f. properties. This is called an AC current or alternating current.

● AC current(Alternating current): Changes its direction after equal intervals of time.

● It is easier to transmit this current over long distances due to lesser loses and hence this is the current that is supplied to our houses from the electricity department with the help of transformers.