Ammeter has the lowest resistance. A galvanometer is converted into an ammeter by using a suitable low resistance shunt in parallel with the galvanometer. The effective resistance of the network when resistors are connected in parallel becomes less than the individual resistance. Hence resistance of ammeter is less than that of galvanometer.
Voltmeter is formbed by connecting a suitable high resistance in series with the galvanometer. Since the effective resistance of the net-work increases when the resistors are connected in series, hence the resistance of voltmeter is more than that of galvanometer.
