Two bulbs, power, voltage, seres connection

math_maj0r

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

Two bulbs rated 25 W - 110 V and 100 W - 110 V are connected in series to a 230 V supply. What will happen?
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2. Relevant equations

p = vi. p = v2/r

3. The attempt at a solution

I am not sure I know how to interpret it correctly. To find the current through bulb 1, I did P1/V1 = 25/110 = .227, and for bulb 2 I did P2/V2 = 100/110 = .909. This can't be right because I1 must equal I2 since they are in series.

If I use the other formula p = v2/r and solve for resistance, i get a really big answer. i think i may be doing something wrong by plugging in 110 for v.

???

Quinzio

You get a big answer ?
How much ?

zgozvrm

First, consider each bulb separately.

If you connect the 25W bulb across a 110V source (as it was designed for), what is the resistance?

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