If voltage decreases and resistance remains the same, what happens to current?

• A. Current stays the same
• B. Current decreases
• C. Not enough information
• D. Current increases

Answer: (B)

Voltage, current, and resistance follow Ohm's law: current equals voltage divided by resistance. If the resistance stays the same and the voltage decreases, the current must decrease as well because you’re dividing a smaller voltage by the same amount of resistance. For example, with a constant 5-ohm load, dropping from 10 V to 5 V changes the current from 2 A to 1 A. So the current decreases. The other options don’t fit: the current wouldn’t stay the same unless the voltage didn’t change or the resistance adjusted perfectly; not enough information isn’t correct because the relationship is fully determined by the given voltage and resistance; and current wouldn’t increase unless the voltage increased or the resistance decreased under the same conditions.