How do you think the brightness of two lamps arranged in parallel compares with the brightness of two lamps arranged in series (both arrangements having one cell)?

How can you change the brightness of the lamps?

Consider the circuit given below where A, B and C are three identical light bulbs of constant resistance.

(a) List the bulbs in order of increasing brightness.

(b) If C burns out, what will be the brightness of A now compared with before?

(c) If B burns out instead, what will be the brightness of A and C compared with before?

If current flows through two lamps arranged:

(a) in series,

(b) in parallel,

and the filament of one lamps breaks, what happens to the other lamp? Explain your answer

The figure below shows a variable resistor in a dimmer switch.

How would you turn the switch to make the lights:

(a) brighter, and

(b) dimmer?

Explain your answer.