A galvanometer has a coil with a resistance of $24.0 \Omega$, and a current of $180 \mu \mathrm { A }$ causes full-scale deflection. If the galvanometer is to be used to construct an ammeter that deflects full scale for $10.0 \mathrm {~A}$, what shunt resistor is required?
A) $423 \mu \Omega$
B) $432 \mu \Omega$
C) $234 \mu \Omega$
D) $342 \mu \Omega$

Question

Quizplus · Accepted Answer

The shunt resistor $ R_s $ is calculated using the formula $ R_s = \frac{R_g \cdot I_g}{I - I_g} $, where $ R_g = 24.0 \Omega $, $ I_g = 180 \mu A $, and $ I = 10.0 A $. Substituting these values gives $ R_s = \frac{24.0 \times 180 \times 10^{-6}}{10 - 180 \times 10^{-6}} \approx 432 \mu \Omega $.

A Galvanometer Has a Coil with a Resistance Of 24.0Ω24.0 \Omega24.0Ω

A Galvanometer Has a Coil with a Resistance Of $24.0 \Omega$