Question

Will the bulb in the two circuits glow with the same brightness?

• A. Yes
• B. No, increased brightness in parallel connection
• C. No, decreased brightness in parallel connection
• D. Data insufficient

Answer 1

The correct option is B No, increased brightness in parallel connection

A bulb is just a high resistance wire which converts electricity into light energy, the more the current, intenser the brightness.
In this case, let us consider that there are 3 bulbs that are connected in series in an electrical circuit. The total resistance of resistors in series is equal to the sum of their individual resistances. Hence, the current flowing through the circuit will be one-third of the total current.
Now, let us consider that the 3 bulbs are connected in parallel in an electrical circuit. The total resistance will always be less than the value of the smallest resistance. Hence, the current flowing through the circuit will be 3 times more than the serially connected circuit. The principle of current in parallel circuits is that the current outside the branches is equal to the sum of the current in the individual branches.
Therefore, the bulbs that are connected in parallel circuit will glow more brightly than the bulbs connected in a serial circuit as the amount of current is more in parallel circuits.