Question
How is a galvanometer converted into a voltmeter and an ammeter? Draw the relevant diagrams and find the resistance of the arrangement in each case. Take resistance of galvanometer as G.
✓
Answer
A galvanometer is converted into a voltmeter by connecting a high resistance ‘R’ in series with it. A galvanometer is converted into an ammeter by connecting a small resistance (called shunt) in parallel with it.
Resistance of voltmeter, 𝑅𝑉 = G + R
Resistance for Ammeter, $\text{R}_{A} = \frac{\text{G }\text{ r}_{s}}{\text{G} + \text{r}_{s}}$.
Resistance of voltmeter, 𝑅𝑉 = G + R
Resistance for Ammeter, $\text{R}_{A} = \frac{\text{G }\text{ r}_{s}}{\text{G} + \text{r}_{s}}$.
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