Question

A galvanometer coil has a resistance of 15 W and the metre shows full scale deflection for a current of 4 mA. How will you convert the metre into an ammeter of range 0 to 6 A?

Answer 1

Hey Dear,

◆ Answer -

Galvanometer is converted to ammeter by adding shunt resistance of 0.01 Ω.

● Explaination -

# Given -

Rg = 15 Ω

Ig = 4 mA = 4×10^-3 A

I = 6 A

Rs = ?

# Solution -

Shunt resistance added to convert galvanometer to ammeter is calculated by -

Rs = Ig.Rg / (I-Ig)

Rs = 4×10^-3 × 15 / (6 - 4×10^-3)

Rs = 6×10^-2 / (6-0.004)

Rs = 0.01 Ω

Therefore, a shunt resistance of 0.01 Ω need to be connected parallel to the galvanometer.

Hope this is helpful...