Three light bulbs of $40\, W$, $60\, W$ and $100\, W$ are connected in series with $220\, V$ source. Which one of the bulbs will glow brightest ............ $W$
A$40$
B$60$
C$100$
D
All with the same brightness
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A$40$
a (a) In series ${P_{Consumed}} \propto {\rm{Brightness}} \propto \frac{1}{{{P_{Rated}}}}$
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