# Bulb Brightness

**1. The problem statement, all variables and given/known data**

Normally, household lightbulbs are connected in parallel to a power supply. Suppose a 40 W and a 60 W lightbulb are, instead, connected in series. (see here) Which bulb is brighter?

**2. Relevant equations**

[tex]P_{resistor}=I\Delta V=I^2R =\frac{(\Delta V)^2}{R}[/tex]

**3. The attempt at a solution**

I have found out the answer is the 40 W light bulb but am not sure why. Since both bulbs are getting the same current it means the 60 W has a higher resistance according to the formula [tex]P=I^2R[/tex] Doesn’t a higher resistance mean more energy dissipated means more light given off? Or am I thinking about it wrong?

Thanks

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