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Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: For measuring the potential difference across a resistance of 600 Ω, the voltmeter with resistance 1000 Ω will be preferred over voltmeter with resistance 4000 Ω. Reason R: Voltmeter with higher resistance will draw smaller current than voltmeter with lower resistance. In the light of the above statements, choose the most appropriate answer from the options given below:

1. Both A and R are correct but R is not the correct explanation of A
2. Both A and R are correct but R is the correct explanation of A
3. A is not correct but R is correct
4. A is correct but R is not correct

Correct answer: A is not correct but R is correct

Solution

The assertion is incorrect because a voltmeter with a higher resistance (4000 Ω) is actually preferred for measuring potential difference across a resistance of 600 Ω, as it minimizes the current drawn from the circuit, leading to a more accurate measurement. The reason is correct because a higher resistance voltmeter indeed draws less current.

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