Basic conceptual Questions: Two light bulbs of 90 watt and 45 watt are connected to a 230 volt source Which one will glow brighter

Statement: Two light bulbs having the watt rating of 90 watts and 45 watts are connected in series with a 230-volt source (wall socket). Which bulb will glow brighter?
Power is rated for 230-volt input.
two-light-bulbs-of-90-watt-and-45-watt-are-connected-to-a-230-volt-source-which-one-will-glow-brighter
Solution:
We can calculate the resistance by using the Ohm's law.

From Ohm's law: R = V2/P

For first bulb: R = (230)2/90 watts = 587 Ω

For first bulb: R = (230)2/45 watts = 1175 Ω

The overall current flowing through the circuit will be:

I = V/R  = 230/1762 = 0.130 A

In present case, the actual power consumed by the lamps can be calculated by the equation, P = I2R

For 90 > P = (0.130)2 * 587 Ω = 10 watt

For 45 > P = (0.130)2 * 1175 Ω = 19.85 watt

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