If a circuit contains a 12v battery and two 3 bulbs in series

If the resistance of each bulb is 3 ohms, and they are connected across the battery, then current will flow through them.

In series, the two 3-ohm bulbs will look like a single 6-ohm resistance.

Current = (voltage) / (resistance) = (12v) / (6 ohms) = 2 Amperes.

The battery will need to deliver some power to the circuit.

Power = (voltage) x (current) = (12v) x (2 Amperes) = 24 watts.

Each bulb will dissipate 12 watts, in the form of light and heat.

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