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 , the voltmeter with resistance will be preferred over voltmeter with resistance .
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.
Assertion A: For measuring the potential difference across a resistance of , the voltmeter with resistance will be preferred over voltmeter with resistance .
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.
- (A)A is not correct but R is correct✓ Correct
- (B)Both A and R are correct and R is the correct explanation of A
- (C)Both A and R are correct but R is not the correct explanation of A
- (D)A is correct but R is not correct
Answer: (A)
Solution
A voltmeter draws current from the circuit, and the smaller that current the less it disturbs the reading, so a higher-resistance voltmeter gives a more accurate measurement. The voltmeter would therefore be preferred over the one across the resistance, which makes the assertion wrong. The reason, that a higher-resistance voltmeter draws a smaller current, is a correct statement. Hence the assertion is not correct but the reason is correct.
JEE Main · 2023 · 01 Feb 2023 · Shift 2 · Single correct option