If a 12 V battery is connected to a 6 Ω resistor, what is the current?

If a 12 V battery is connected to a 6 Ω resistor, what is the current?

• A. 1 A
• B. 3 A
• C. 2 A
• D. 0.5 A

Answer: (C)

Ohm's law: current through a conductor equals the voltage across it divided by its resistance. I = V / R. Here, V = 12 V and R = 6 Ω, so I = 12 / 6 = 2 A. That means 2 amperes flow through the resistor, from the battery’s positive terminal toward the negative one. If you wanted, you could also note the power dissipated is P = I^2R = 4 × 6 = 24 W, for a sense of the energy involved.

Ohm's law: current through a conductor equals the voltage across it divided by its resistance. I = V / R.

Here, V = 12 V and R = 6 Ω, so I = 12 / 6 = 2 A. That means 2 amperes flow through the resistor, from the battery’s positive terminal toward the negative one. If you wanted, you could also note the power dissipated is P = I^2R = 4 × 6 = 24 W, for a sense of the energy involved.