Question

Humberto builds two circuits using identical components.

Circuit 1: A series circuit with three lightbulbs
Circuit 2: A parallel circuit with three lightbulbs

He then adds two more lightbulbs in a series with the bulbs in circuit 1 and two more lightbulbs on new branches in parallel with each bulb in circuit 2.

What can he expect to see?

A) All bulbs in circuit 1 will shine at the same brightness as the original bulbs, while all bulbs in circuit 2 will be dimmer than the original bulbs.
B) All bulbs in circuit 1 will shine more dimly than the original bulbs, while all bulbs in circuit 2 will have the same brightness as the original bulbs.
C) The original bulbs will remain at their original brightness, but the bulbs added to circuit 1 will be dimmer than the bulbs added to circuit 2.
D) The original bulbs will remain at their original brightness, but the bulbs added to circuit 1 will be brighter than the bulbs added to circuit 2.

Answer 1

B) All bulbs in circuit 1 will shine more dimly than the original bulbs, while all bulbs in circuit 2 will have the same brightness as the original bulbs.

Step-by-step explanation:

When we connect more bulbs in circuit 1 where all are connected in series then the net resistance of the circuit will increase and voltage across each bulb will decrease.

So as per the formula

`P = (V^2)/(R)`

so here since voltage decreases across each bulb so we can say that power across each bulb will decrease and bulb gets more dimmy then initially connected bulbs

When we connect bulbs in parallel then voltage across each bulb will remain same and then the brightness of each bulb will remain constant.

So correct answer will be

B) All bulbs in circuit 1 will shine more dimly than the original bulbs, while all bulbs in circuit 2 will have the same brightness as the original bulbs.

Answer 2

Humberto should expect to see that all bulbs in circuit 1 will shine more dimly than the original bulbs, while all bulbs in circuit 2 will have the same brightness as the original bulbs.

B) All bulbs in circuit 1 will shine more dimly than the original bulbs, while all bulbs in circuit 2 will have the same brightness as the original bulbs.