Question

Two identical electric bulbs are connected in series and then to a battery. The third identical bulb then is connected in parallel to the line of first two bulbs. This additional connection will:

Increase the illumination produced by bulbs connected in series

Decrease the illumination produced by bulbs in series

Leave the illumination produced by bulbs in series unchanged

It will change illumination somehow, but we need to know the voltage on battery and resistances of bulbs to answer.

Answer 1

We know that the current in the series connection is same everywhere across every element hence when the bulbs are connected in series the bulbs glow with lower brightness as the number of bulb increases.

In other words as the number of bulbs increases in series the bulbs brightness of the bulb starts to reduce. As we are given that bulbs are identical hence their resistance is same. And we know that in parallel connection the current is divided hence when an additional bulb is connected to the two bulbs in series parallel to them the current is distrubed hence lower value of current will flow and hence the brightness of the bulb will be reduced.

So in conclusion to the above thing is that the bulb illumination will be reduced when we connect a bulb in parallel. The third bulb irrespective of the resistance value will be indugled in division of current hence lower value of current will be propagated so the bulbs will reduce its brightness.

So option 2 is the right answer.

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