Two identical bulbs A and B are designed for same voltage. Their power rating are Pa and Pb respectively, where Pb > Pa. They are joined in series across a V voltage supply, then which bulb will draw more power

@ vrinda 
as per the joules law of heating 
P= I SQUARE R 
P= VI 
so, by applying that if we take V as a constant , then we can say 
p is directly proportional to i 
and here in the question u havenot mention the current drawn by each bulb , the only thing given is the power rating , so, 
by that the power rating will be increase if it have more current passed through it .. 
for example – a 60 w cfl bulb will draw more current than the 10 w led bulb obviously .. 
so, acc to that logic BULB B will draw more power than BULB A .. 
HOPE IT CLEARS YOUR DOUBT 

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