A galvanometer of 60Ω resistance shows full scale deflection for a current of 8 mA. The shunt required to convert the galvanometer into an ammeter of range 0 to 6 A will be: |
$4.67 × 10^{-2}Ω$ $5.67 × 10^{-2}Ω$ $2.67×10^{-2}Ω$ $8 × 10^{-2}Ω$ |
$8 × 10^{-2}Ω$ |
The correct answer is Option (4) → $8 × 10^{-2}Ω$ $R_g$, Resistance of galvanometer = 60 Ω $I_g$, full scale deflection current = 8 mA $I_{max}$, Desire Ammeter range = 6A ∴ Current in Shunt Resistance, $I_{shunt}=6A-0.008A=5.992A$ ∴ Voltage across the galvanometer, $V_g=I_g×R_g$ [By ohm's law] $=0.008×60$ $=0.48V$ $V_{shunt}=V_g=0.48V$ $R_{shunt}=\frac{V_{shunt}}{I_{shunt}}=\frac{0.48}{5.992}=0.08Ω$ |