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प्रश्न
How is the working of an electric bell affected, if alternating current be used instead of direct current?
उत्तर
If an A.C. source is used in place of a battery, the core of the electromagnet will get magnetized, but the polarity at its ends will change. Since the attraction of the armature does not depend on the polarity of the electromagnet, the bell will still ring on pressing the switch.
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संबंधित प्रश्न
Why is soft iron used as the core of the electromagnet in an electric bell?
The incomplete diagram of an electric bell is given in Figure. Draw winding of coil on the core and complete the electric circuit in the diagram.
G-Gong, H-Hammer, A-Armature, C-Core, B-Battery.
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