question_answer

A galvanometer, whose resistance is 50 ohm, has 25 divisions in it. When a current of \[4\times {{10}^{-4}}\]A passes through it, its needle (pointer) deflects by one division. To use this galvanometer as a voltmeter of range 2.5 V, it should be connected to a resistance of- [JEE Main 12-Jan-2019 Evening]

A) 200 ohm

B) 6250 ohm

C) 6200 ohm

D) 250 ohm

Correct Answer: A

Solution :

[a] The full scale deflection current

Let R be the resistance connected