Calculate New Power when adding a Resistor

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AI Thread Summary
A user is trying to calculate the total power dissipated when adding a second resistor, R2 = 20Ω, in series with an initial resistor, R1 = 23Ω, which dissipates 44W. They initially calculated the current through R1 to be 1.38A and found the equivalent resistance of the series circuit to be 43Ω. However, their power calculation using P=I²R resulted in 82W, which was incorrect. They were advised to calculate the battery voltage first, as it remains constant when adding resistors in series. The user ultimately realized their misunderstanding regarding the current and confirmed their solution.
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As this is my first post please feel free to correct me if I am posting this is the wrong section or on improper etiquette in general. I'm having a bit of trouble with what should be a pretty simple problem.

Homework Statement


A resistor R1 = 23Ω is connected to a battery that has negligible internal resistance and electrical energy is dissipated by at a rate of 44W.

If a second resistor R2 = 20Ω is connected in series with R1 , what is the total rate at which electrical energy is dissipated by the two resistors?

Homework Equations


P=VI=I2R, V=IR

The Attempt at a Solution



I first solved for the current I by using the equation P=I2R using my R1. I found the current to be I=1.38A.

From there I found the equivalent resistance by adding my resistances as they are in series to get an equivalent resistance of 43Ω.

I then used the equation P=I2R plugging in the 1.38A and 43Ω.
This gave me a new power of 82W but the site says this is not correct. Any suggestions?
 
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Try calculating the battery voltage in the first calculation.

This will stay constant for the second calculation.
 
Thanks! I got it! I had it in my head that the current would be what remained constant since it was in series but wasn't quite sure about that. Thanks again!
 
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