Alberta Boilers Safety Association (ABSA) Practice Test

If the resistance in a circuit remains constant and the applied voltage is increased, what will happen to the current?

1. A corresponding decrease in current

2. No change in current

3. Corresponding increase in current

4. Small change in resistance

The correct answer is: Corresponding increase in current

When resistance in a circuit is kept constant and the applied voltage increases, the current will increase in proportion to the voltage. This relationship is described by Ohm's Law, which states that current (I) is equal to voltage (V) divided by resistance (R) – in formula terms, I = V/R. Since resistance does not change in this scenario, increasing the voltage leads to a direct increase in current. Essentially, as the voltage rises, more electrical potential is available to drive the flow of electrons through the circuit, resulting in an increase in the current flow. In contrast, if the resistance were to change, it would influence how current behaves, but since the problem specifically outlines a constant resistance, we can confidently say that the current will vary directly with voltage changes, demonstrating that option C is indeed the appropriate answer.