Suppose you had one circuit with a 9V battery connected to two 100 ohm light bulbs in series. and a second circuit with a 9V battery connected to two 100 ohm light bulbs in parallel. How does the brightness of the two bulbs in series compare to two bulbs connected in parallel? Which set is dimmer? Explain why.

Bulbs in series will be dim

Explanation:

The voltage remain constant in a series circuit, thus bulbs in series circuit will get equally distributed voltage which is not equal to the voltage across the circuit or the voltage supplied

In case of parallel circuit, the voltage across the bulb is the same as the voltage across the circuit due to which bulbs will be brighter in case of parallel circuit