Question

30bulbs are connected in series. if one bulb fused and the remaining 29 bulbs are joined in series and connected to the same supply the light in the room will be

Answer 1

I think the answer is remins the same or increases.......

Answer 2

there would be no light in the room from these bulbs because if one bulb is fused then the circuit is opened and no current flows through the circuit and then no bulb glows.
This is the concept of series combination that is the circuit is opened or if any one appliances get fused then no other appliances work.