Question

in a series circuit what happens when one bulb burns out

Answer 1

The same current flows through each part of a series circuit. ... In the same way, if one of the bulb was unscrewed, the current flow to both the bulbs would be interrupted. If the circuit were a string of light bulbs, and one burned out, the remaining bulbs would also turn off.

Answer 2

When one bulb burns out, the circuit is broken