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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