Solving Energy Dissipation in Lightbulbs Connected to a Power Line

AI Thread Summary
The discussion focuses on calculating the energy dissipation in lightbulbs rated at 40 W, 60 W, and 100 W connected to a 120 V power line. To solve the problem, the relevant equation for power dissipation, Pr = (Vrms)^2/R, is utilized to determine the resistance of each bulb. The voltage across each bulb remains constant, allowing for the calculation of equivalent resistance and current in each branch. The energy dissipated in each lamp can then be found using the formula I^2*R. The conversation emphasizes understanding the relationship between power, resistance, and energy dissipation in electrical circuits.
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Homework Statement



Lightbulbs labeled 40 W, 60W, and 100 W are connected to a 120 V/60 Hz power line as shown in the diagram. What is the rate at which energy is dissipated in each bulb?



Homework Equations



Pr = (Vrms)^2/R

The Attempt at a Solution



I'm not exactly sure how to get this one started. Do I have to make some sort of equivalency lightbulb? Can somebody please point me in the right direction?
 

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Voltage across each branch is the same. Using the relevant equation find the resistance of each lamp.

Find the equivalent resistance of the circuit and the current in each branch.

Energy dissipated in each lamp is given by I^2*R.

Now proceed.
 
Thanks a bunch rl.bhat!
 

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