Chemistry
Assertion (A): For electrical heating devices like electric iron and heater, alloys are used.
Reason (R): Alloys have a greater resistance and low melting point.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Metallurgy
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Answer
Both A and R are true but R is not the correct explanation of A.
Explanation — Alloys are used for heating devices like electric iron and heater because of its high resistance to electricity. Hence, assertion (A) is true. Generally alloys have great resistance to electricity. Thus, they can produce more heat and alloys also have lower melting point than its individual component. Hence, reason (R) is true.
However, in case of electrical iron and heater, alloys have high melting point to withstand the heat, Hence, reason (R) is not correct explanation of assertion (A).
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