A galvanometer having a coil resistance 100 $\Omega$ gives a full scale deflection when a current of 1 mA is passed through it. What is the value of the resistance which can convert this galvanometer into a voltmeter giving full scale deflection for a potential difference of 10 V?
Solution
i<sub>g</sub> = 1 mA , R<sub>g</sub> = 100 $\Omega$
<br><br>V = i<sub>g</sub>(R + R<sub>g</sub>)
<br><br>$\Rightarrow$10 = 1 × 10<sup>–3</sup> (R + 100)
<br><br>$\Rightarrow$R = 9.9 k$\Omega$
About this question
Subject: Physics · Chapter: Current Electricity · Topic: Ohm's Law and Resistance
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