Question

What happens in this circuit if one of the light bulbs is unscrewed?

Answer 1

We can actually tell from the question that the light bulbs are connected in series.

One light bulb was unscrewed. Since they're in series, ALL of the light bulbs go out.

THAT's obviously the reason why we can't SEE the circuit !

Answer 2

Step-by-step explanation:

If the circuit is broken at any point there won't be any current that will flow. ... 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