In a circuit with a 12 V source and a 3 Ω resistor in series, what is the current?

In a circuit with a 12 V source and a 3 Ω resistor in series, what is the current?

• A. 4 amperes
• B. 1 ampere
• C. 12 amperes
• D. 0.33 amperes

Answer: (A)

Ohm’s law is being tested here: current equals voltage divided by resistance. In this simple setup, the 12 V source is applied across a 3 Ω resistor, so the current through the circuit is I = 12 V / 3 Ω = 4 A. This is the value that matches the given voltage and resistance. The other numbers come from using different denominators or misapplying the division, but with the stated values the correct result is 4 amperes.

Ohm’s law is being tested here: current equals voltage divided by resistance. In this simple setup, the 12 V source is applied across a 3 Ω resistor, so the current through the circuit is I = 12 V / 3 Ω = 4 A. This is the value that matches the given voltage and resistance. The other numbers come from using different denominators or misapplying the division, but with the stated values the correct result is 4 amperes.