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Science · 2024 · 2 marks
CBSE 2024 · Region 4 · Set 2 · Q26
State Joule's law of heating. How is this effect useful in electric circuits where fuse is used as a safety device?
State Joule's law of heating. How is this effect useful in electric circuits where fuse is used as a safety device ?
Marking-scheme solution
Joule's Law - Heat produced in a resistor is directly proportional to:
-Square of current for a given resistance
-Resistance for a given conductor and
-Time for which the current flows though the resister,
If any unduly high electric current flows through the circuit, the temperature of the fuse wire increases. This melts the fuse wire and breaks the circuit.
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CBSE Class 10 Science past-paper question from the 2024 board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.