Consider the circuit given below where A, B and C are three identical light bulbs of constant resistance.
  1. List the bulbs in order of increasing brightness.
  2. If C burns out, what will be the brightness of A now compared with before?
  3. If B burns out instead, what will be the brightness of A and C compared with before?
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  1. C will be the brightest. Voltage will be distributed equally between A and B, so they will have equal brightness but lesser than that of C.
  2. A gets the same voltage as before, so its brightness remains the same.
  3. If B burns put, A will also stop glowing because it is connected in series with B. However, brightness of C remains the same.
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