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## Homework Statement

Three 80.0 W, 135 V lightbulbs are connected across a V = 135 V power source, as shown in Figure P18.48. (Assume that the resistance of each bulb is constant even though, in reality, the resistance increases markedly with current.)

http://www.webassign.net/sercp/p18-48alt.gif

(a) Find the total power delivered to the three bulbs. W

(b) Find the potential difference across each light bulb.

deltaVR1 = V

deltaVR2 =

deltaVR3 =

## Homework Equations

I^2R = P

DeltaV = IR

DeltaV/I = R

p/v = I

## The Attempt at a Solution

The first thing I did was find the current which is

**80/135 = .5925**. From this I found the resistance which is

**135/.5925 = 227.85 ohm.**

From there I tried using the formula I^2R= P, which gave me the incorrect answer. Then I thought since R2 and R3 are parallel I can combine it by using the formula 1/R = 1/R1 + 1/R2. But that got me a bit confuse and still gave me an incorrect answer.

I am not sure where to start and what steps I am doing wrong or missing. Any help would be great.