Question

A simple circuit contains an ideal battery and a resistance R. If a second resistor is placed in parallel with the first:
A) The potential across R increases.
B) The power dissipated by R will increase.
C) The current delivered by the battery will increase.
D) None of these.

Answer 1

Hint: The voltage across the resistor in parallel always remains constant but the current in the two circuits will be different. The total current in the circuit will be equal to the addition of the current of the current in the two resistors.

Complete step by step solution:
It is given that the circuit has a battery and a resistor in the beginning but after that a second resistor is placed in the circuit in parallel connection. The circuit will have some current in the circuit with resistor R but after the resistor is placed in parallel with the initial resistor then the potential difference across the resistors will be the same but the current in the two resistors will be different. As there was originally current flowing in the circuit due to a resistor but due to addition of another resistor now the current has to also flow from another circuit which means that we require more power from the battery because more power will provide more current in the circuit which can be then supplied in to the another resistor on the circuit.

The current delivered by the battery increases so the correct answer is option C.

Note: If the resistor is connected in series then the potential difference across the resistor will be different but the current in the two resistors will be same but if the circuit is parallel then the current in the two circuits will be different but the potential difference will be same. The resistance dissipates the energy of the circuit by creating hurdles in the flow of the current.