What is shunt? Obtain the formula for the shunt.

Explanation

1. Low value resistor connected across galvanometer is known as shunt.

Equation of shunt :
2. Resistance of galvanometer be `R_(G)` and current flowing through it is `I_(G)`.
3. Resistance of shunt be `r_(s)` and current flowing through it is `(I-I_(G))`.
4. Apply Kirchhoff.s law in loop,
A-B-C-D-A,
`-I_(G)R_(G)+r_(s)(I-I_(G))=0`
`thereforer_(s)=(R_(G)I_(G))/((I-I_(G)))`
(I = current capacity of ammeter, `I_(G)` = current capacity of galvanometer)