Question

A galvanometer has a resistance G and a current I_g flowing in it produces full scale deflection. S₁ is the value of the shunt which converts it into an ammeter of range 0 to I and S₂ is the value of the shunt for the range 0 to 2I. The ratio is :

• A. $\frac { S _ { 1 } } { S _ { 2 } }$ = $\left( \frac { 2 \mathrm { I } - \mathrm { I } _ { \mathrm { g } } } { \mathrm { I } - \mathrm { I } _ { \mathrm { g } } } \right)$
• B. $\frac { S _ { 1 } } { S _ { 2 } }$ =$\frac { 1 } { 2 }$ $\left( \frac { \mathrm { I } - \mathrm { I } _ { \mathrm { g } } } { 2 \mathrm { I } - \mathrm { I } _ { \mathrm { g } } } \right)$
• C. 2
• D. 1

Answer 1

Answer: (A)

$\frac { S _ { 1 } } { S _ { 2 } }$ = $\left( \frac { 2 \mathrm { I } - \mathrm { I } _ { \mathrm { g } } } { \mathrm { I } - \mathrm { I } _ { \mathrm { g } } } \right)$

Answer 2

S₁= , S₂ = ̃ =