Which is correct about an ammeter?

a. The internal resistance must be much greater than the other resistances in the circuit.
b. The internal resistance must be much smaller than the other resistances in the circuit.
c. The internal resistance must be comparable to the other resistances in the circuit.

b. The internal resistance must be much smaller than the other resistances in the circuit.

Explanation:

Ammeter is used to measure the current flowing through a circuit. It is connected in series configuration with the load. In such a scenario the resistance of the ammeter should be negligible so as to make sure that the voltage drop across the resistance of ammeter is zero and it shows the correct reading of the current in the circuit.