Question

Assertion : Out of galvanometer, ammeter and voltmeter, resistance of ammeter is lowest and resistance of voltmeter is highest
Reason : An ammeter is connected in series and a voltmeter is connected in parallel, in a circuit

• A. Both (A) and (R) are true and (R) is the correct explanation of A
• B. Both (A) and (R) are true but (R) is not the correct explanation of A
• C. (A) is true but (R) is false
• D. (A) is false but (R) is true

Answer 1

The correct option is B Both (A) and (R) are true but (R) is not the correct explanation of A

Out of galvanometer , ammeter and voltmeter the resistance of ammeter is lowest and resistance of voltmeter highest the actual reason is to measure the current passing through the circuit the Ammeter should be connected in series. If it has considerable amount of resistance then the current that it measure will differ from the actual current passing through it. So it must be of low resistance.

In the case of Voltmeter it is connected parallel to the load. To get the accurate value zero amount of current pass through voltmeter. So it must be of high resistance.

therefore the reason behind low and high value of resistances of ammeter and voltmeter is to achieve the best correct reading , not the placement of them in series and parallel.