A galvanometer of resistance 15Ω gives full scale deflection for a current of 2 mA. Calculate the shunt resistance needed to convert it into an ammeter of range 5 A

Question

A galvanometer of resistance 15Ω gives full scale deflection for a current of 2 mA. Calculate the shunt resistance needed to convert it into an ammeter of range 5 A (A)  0.178 Ω  (B)  0.002 Ω  (C)  0.006 Ω  (D)  5 Ω

Tardigrade Admin · Accepted Answer

Resistance of shunt needed to convert it into ammeter is S =(Ig G/I-Ig) =(2 × 10-3 × 15/5-2 × 10-3)=0.006 Ω

Q. A galvanometer of resistance $15Ω$ gives full scale deflection for a current of $2 m A$ . Calculate the shunt resistance needed to convert it into an ammeter of range $5 A$

$0.178 Ω$

$0.002 Ω$

$0.006 Ω$

$5 Ω$

Resistance of shunt needed to convert it into ammeter is
$S = \frac{I _{g} G}{I - I _{g}}$
$= \frac{2 \times 1 0 ^{- 3} \times 15}{5 - 2 \times 1 0 ^{- 3}} = 0.006 Ω$

Q. A galvanometer of resistance 15Ω gives full scale deflection for a current of 2mA. Calculate the shunt resistance needed to convert it into an ammeter of range 5A

0.178Ω

0.002Ω

0.006Ω

5Ω