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Question
What is an ‘electric fuse’? State its two characteristics of electric fuse.
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Solution
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.
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