What will happen to the current in a circuit if the resistance is doubled?

• A. The current will remain the same
• B. The current will be doubled
• C. The current will be halved
• D. The current will be tripled

Answer: (C)

When the resistance in a circuit is doubled, the current will decrease. This relationship is described by Ohm's Law, which states that current (I) is equal to voltage (V) divided by resistance (R): I = V/R.

If the voltage remains constant and the resistance is increased, the denominator of the equation becomes larger, leading to a smaller current. Specifically, if resistance is increased from R to 2R, you can see the effect on the current:

Initial current = V/R

New current = V/(2R) = (1/2)(V/R)

This shows that the current will be half of the original amount when the resistance is doubled. Therefore, selecting that the current will be halved accurately reflects the fundamental principle of how resistance affects current in a circuit.