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प्रश्न
Explain the importance/uses of fuse wire.
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उत्तर
- Fuse is an important application of heating effect of electric current used in electric circuits.
- It protects circuits and appliances by stopping the flow of any excess electric current.
- If a current larger than the specific value flows through the circuit, the temperature of fuse wire increases. This melts the fuse wire and breaks the circuit.
- In summer season, when consumption of electrical power is huge in the evening due to home lighting, fan, air conditioner, use of electricity in shops etc, an excessive current is drawn from the transformer. If the capacity of the transformer is insufficient, its fuse wire melts, and the supply gets shut down.
संबंधित प्रश्न
Write Joule's law of heating.
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Why is a series arrangement not used for connecting domestic electrical appliances in a circuit?
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How much heat will an instrument of 12 W produce in one minute if it is connected to the heat produced by it?
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The heat produced in a wire of resistance 'x' when a current 'y' flows through it in time 'z' is given by:
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(d) y × z × x
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Right or wrong sentence.
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Write scientific reason.
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Name any two appliances which work under the principle of heating effect of current.
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Anannya responded to the question: Why do electrical appliances with metallic bodies are connected to the mains through a three-pin plug, whereas an electric bulb can be connected with a two-pin plug?
She wrote: Three-pin connections reduce heating of connecting wires.
- Is her answer correct or incorrect? Justify.
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