Kaplan Nursing Entrance Practice Exam

In a circuit, what does an increase in resistance typically do to current, according to Ohm's Law?

1. Increases current

2. Decreases current

3. Has no effect on current

4. Increases voltage

The correct answer is: Decreases current

According to Ohm's Law, which states that voltage (V) equals the product of current (I) and resistance (R) — expressed mathematically as V = I × R — an increase in resistance will lead to a decrease in current if the voltage remains constant. This relationship implies that if you increase the resistance in a circuit while keeping the voltage steady, the current will have to decrease to maintain the balance in the equation. In a practical sense, resistance can be thought of as a restriction to the flow of current. When resistance rises, it creates more opposition for the flow of electrons, which translates to a lower current. This fundamental principle governs how electrical circuits operate and explains the inverse relationship between resistance and current when voltage does not change.