What happens when you add a light bulb in a series circuit?

High resistance bulbs are brighter in series circuits. If two bulbs in series aren't identical then one bulb will be brighter than the other. Brightness depends on both current and voltage. Remember the current through both must be the same because the current is the same everywhere in a series circuit. read more

A series circuit can be constructed by connecting light bulbs in such a manner that there is a single pathway for charge flow; the bulbs are added to the same line with no branching point. As more and more light bulbs are added, the brightness of each bulb gradually decreases. read more

Please stop answering. You are incorrect. IN SERIES: Resistance is additive. A portion of the total voltage is dropped across each light bulb. Current drops. For example, three 60 watt bulbs are connected in series against a 120V source. V = IR, P=VI. First, determine the resistance of a single bulb. read more