A moving coil galvanometer of resistance is used as an ammeter using a resistance . The maximum deflection current in the galvanometer is . Find the minimum current in the circuit so that the ammeter shows maximum deflection. [2005]

Question

A moving coil galvanometer of resistance $100 Ω$ is used as an ammeter using a resistance $0.1 Ω$ . The maximum deflection current in the galvanometer is $100 μ A$ . Find the minimum current in the circuit so that the ammeter shows maximum deflection. [2005]

Smart Achievers · Accepted Answer

(1)

$Here, I_{g} = 100 \times 10^{- 6} A, G = 100 Ω, S = 0.1 Ω$

$Using I_{g} G = (I - I_{g}) S$

$I = I_{g} (\frac{G}{S} + 1)$ $= 100 \times 10^{- 6} (\frac{100}{0.1} + 1)$

$= 100 \times 10^{- 6} (1000 + 1)$

$= 100 \times 10^{- 6} \times 1001$

$= 100.1 \times 10^{- 3} A$

$∴$ $I = 100.1 mA$

Solution

Q.
A moving coil galvanometer of resistance $100 Ω$ is used as an ammeter using a resistance $0.1 Ω$ . The maximum deflection current in the galvanometer is $100 μ A$ . Find the minimum current in the circuit so that the ammeter shows maximum deflection. [2005]

1 100.1 mA

2 1000.1 mA

3 10.01 mA

4 1.01 mA

Want Us to Email you About Special Offers & Updates?