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प्रश्न
Assertion (A): Alloys are commonly used in electrical heating devices like electric iron and heater.
Reason (R): Resistivity of an alloy is generally higher than that of its constituent metals but the alloys have low melting points then their constituent metals.
पर्याय
Both (A) and (R) are true and (R) is correct explanation of the assertion.
Both (A) and (R) are true and (R) is correct explanation of the assertion.
(A) is true but (R) is false.
(A) is false but (R) is true.
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उत्तर
(A) is true but (R) is false.
Explanation:
Alloys (e.g., nichrome) are used in electric irons and heaters because they have higher resistivity, so they produce heat efficiently for a given current. The reason statement is false about melting points, heating-element alloys are chosen to have high melting points (so they don’t melt), so the claim that alloys generally have lower melting points than their constituent metals is incorrect.
