A galvanometer has a resistance of 20 Ω and reads full-scale when 0.2 V is applied across it. To convert it into a 10 A ammeter, the galvanometer coil should have a
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A galvanometer has a resistance of 20 Ω and reads full-scale when 0.2 V is applied across it. To convert it into a 10 A ammeter, the galvanometer coil should have a

G1 Physics · Accepted Answer

Treat an ideal voltmeter as open circuit and an ideal ammeter as zero resistance; for galvanometer conversion use the standard series/shunt resistance relations. The result matches B (0.02 Ω resistor connected across it).