A galvanometer has a current range of 15 m A and a voltage range of 750 mV. To convert this galvanometer into ammeter of range 25 amp the shunt required is

Given that the galvanometer has a current range of 15 mA i.e., ig = maximum current measured =15×10−3 amp. Maximum voltage measured= 750 x 10-3 V∴Galvanometer resistanceG=750×10−315×10−3=50ΩNow S=ii−igG=15×10−3×5025−15×10−3≃0⋅03Ω