In a DC circuit with a 12 V supply and a 10 Ω resistor, what is the current?

• A. 0.12 A
• B. 1.0 A
• C. 2.4 A
• D. 1.2 A

Answer: (D)

Current in a DC circuit is found with Ohm’s law: I = V / R. With a 12 V supply across a 10 Ω resistor, the current is 12 divided by 10, which equals 1.2 A. This means 1.2 coulombs of charge flow per second through the circuit. In a simple loop, the same current travels through every element. The other numerical options would require different resistor values (for example, 0.12 A would come from 100 Ω, 1.0 A from 12 Ω, and 2.4 A from 5 Ω), but with the given values the current is 1.2 A.