Question

A simple series circuit is composed of a 9 volt battery and two 1 ohm resistors and an ammeter (current meter) to measure the current flow in the circuit.





Since the resistors have same resistance (1 ohm), what will happen if one of the resistors is removed from the circuit and is replaced by a wire to complete the circuit?


The current that is moving through the circuit would increase.


The current that is moving through the circuit would decrease.


The voltage of the circuit would increase.


The voltage of the circuit would decrease.

Answer 1

The current would increase.

Reason: initially R = 1 + 1 = 2 Ω so I = 9 V / 2 Ω = 4.5 A. Replacing one resistor with a wire gives R = 1 Ω so I = 9 V / 1 Ω = 9 A. (Battery voltage stays 9 V.)