Physics
Assertion (A) : A thick wire offers less resistance in comparison to a thin wire.
Reason (R) : Resistance of wire is directly proportional to its area of cross-section.
- both A and R are true and R is the correct explanation of A
- both A and R are true and R is not the correct explanation of A
- assertion is false but reason is true
- assertion is true but reason is false
Current Electricity
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Answer
assertion is true but reason is false
Explanation
Assertion (A) is true because in a thick wire, electrons get a larger area of cross-section to flow as compared to a thin wire, therefore, a thick wire offers less resistance.
Reason (R) is false because resistance is inversely proportional to the area of cross-section, not directly proportional since flow of electrons (i.e., current) depends upon the area of cross-section through which they flow so more area implies high current as number of collisions between electrons decreases and vice versa.
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