Question

Q. Name the physical quantity which is (I) same (ii) different ,in all the bulb when three bulbs of :

(A) same wattage are connected in series

(B) same wattage are connected in parallel

(C) different wattage are connected in series

(D) different wattage are connected in parallel

Answer 1

Well... In the question nothing is specified about voltage ratings of bulb are same or different.I assume it as they are same .

So the answer would be :

a)Physical quantity which remains same when some wattage are connected in series :

--->Same wattage , so same voltage then same resistance

--> Same voltage drop means same voltage drop across the bulbs.hence current, potential drop, resistance and luminosity of bulb remains same

Different ---none

b)Same wattage are connected in parallel:Answer would be : same potential drop, current and resistance.Different

--none

c) Different wattage are connected in series:

If wattage is different with same voltage rating then resistance will be different then potential drop also differs.Only electric current remains same.

d)Different wattage are connected in parallel:

If wattage is different with same voltage then the resistance are different too . Current also differs .Luminosity also differs.