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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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The heat produced by passing an electric current through a fixed resistor is proportional to the square of:
(a) magnitude of resistance of the resistor
(b) temperature of the resistor
(c) magnitude of current
(d) time for which current is passed
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(a) tungsten
(b) bronze
(c) nichrome
(d) argon
Which of the following characteristic is not suitable for a fuse wire?
(a) thin and short
(b) thick and short
(c) low melting point
(d) higher resistance than rest of wiring
Identify the figure and give its use.

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Right or wrong sentence.
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Write scientific reason.
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What does overloading cause?
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(c) Give a reason for your answer in (b).
Your teacher has shown you the following activity.

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Write down any three questions that come to your mind about this activity.
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What is a trip switch?
The following is not a safety device.
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The electric fuse works on the Joule heating principle.
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She wrote: Three-pin connections reduce heating of connecting wires.
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