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Question
Observe the following diagram and answer the questions.
- Explain the construction of the equipment shown in the figure.
- How is AC generated?
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Solution
- An AC generator consists of a rotating rectangular coil ABCD placed between the two poles of a permanent magnet. The coil is attached to the two rings R1 and R2 at both ends. The two stationary conducting brushes B1 and B2 are maintained and pushed independently on the corresponding rings R1 and R2.
The coil inside the magnetic field can be rotated mechanically from the outside by turning the two internal rings R1 and R2, which are coupled to an axle. The galvanometer is linked to the two brushes' outer ends to display the direction of current flow in the specified external circuit. - According to Fleming's right-hand rule, the current is induced in these arms in the direction ABCD. After half rotation, arm CD moves down and arm AB moves up. As a result, each segment's current flow switches direction, resulting in net-induced current flowing in the direction of DCBA. As a result, the polarity of the current in each arm changes after every turn, producing an alternating current.
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