Question

The combined resistance of a galvanometer of resistance 500Ω and its shunt is 21Ω. Calculate the value of shunt.

Answer 1

Given:

G = 500Ω

R_eq = 21Ω

To Find:

S = ?

Formula:

1/R_eq = 1/G + 1/S

Solution:

1/R_eq = 1/G + 1/S

1/S = 1/R_eq - 1/G = (G - R_eq)/R_eqG

∴ S = R_eqG/(G - R_eq)

∴ S = 21 × 500/(500 - 21)

∴ S = 10500/479

∴ S = 21.92Ω