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प्रश्न
What is an ‘electric fuse’? State its two characteristics of electric fuse.
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उत्तर
The electric fuse is a safety device in electric circuits, used to limit the current and thus it acts as a safeguard for the household circuit and any electric appliance connected in the circuit from being damaged. Its characteristics are:
(i) It has a low melting point (m.p.) of about 200°C and is usually made from an alloy of 50% tin and 50% lead.
(ii) It has a high resistance so that its temperature rises rapidly and soon exceeds its m.p. and thus breaks it, when current passing through it exceeds the permissible limits. In such a case it acts as a switch.
संबंधित प्रश्न
Explain the meaning of the student 'current rating of a fuse is 5A'.
A fuse is a short piece of wire of high ______ and of material of low ______.
A fuse wire is made of an alloy of ______ and ______. If the current in a circuit exceeds the current rating of the fuse wire, it ______.
How is a fuse put in an electric circuit?
(i) Write one advantage of connecting electrical appliances in parallel combination.
(ii) What characteristics should a fuse wire have ?
(iii) Which wire in a power circuit is connected to the metallic body of the appliance ?
Higher the current rating, _______ is the fuse wire.
How does the thickness of a fuse wire depend on its current rating?
Explain the significance of kWh meter, main switch and main fuse in house-circuiting.
(a) Name the electrical appliance shown in the diagram below.

(b) Name the material of the wire used in this device.
(c) Name two important characteristics of this wire.
Two fuse wires are rated 5 A and 20 A. Which of the two is longer ?
