Alberta Boilers Safety Association (ABSA) Practice Test

In which component does an increase in voltage result in an increase in current?

1. Resistor

2. Capacitor

3. Inductor

4. Transformer

The correct answer is: Resistor

An increase in voltage resulting in an increase in current is a fundamental characteristic of a resistor, described by Ohm's Law, which states that voltage (V) equals current (I) times resistance (R). According to this relationship, when the resistance remains constant, any increase in voltage directly leads to a proportional increase in current. This linear relationship is key to understanding how resistors operate in electrical circuits. In contrast, other components behave differently under changing voltage conditions. A capacitor, for example, stores energy in an electric field and exhibits a varying current based on its charge and the frequency of the applied voltage. An inductor, on the other hand, opposes changes in current due to its magnetic field and can experience an induced voltage that can reduce the net current when voltage increases rapidly. A transformer functions on the principle of electromagnetic induction and transfers energy between circuits at varying voltages and currents, further complicating the linear relationship seen in resistors. Thus, only the resistor will exhibit a direct increase in current with an increase in voltage under constant resistance conditions.