Internal resistance circuit problem

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Sarlizwx
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Homework Statement



In a circuit, two identical batteries with EMF of 22 V and internal resistance of 7 Ohm are placed in parallel to provide power to a load resistance of RL = 35 Ohms. What is the power transferred from the current to RL to heat the resistor?


Homework Equations


Is R(L) (Resistance load) mean the same thing as R(total)? I know EMF = Isys * Rsys as well.



The Attempt at a Solution



Only drew the diagram, labeled areas and put the RL = [1/R(1) + 1/R(2)] ^ -1I also know that Itot = I1 + I2. I'm assuming here that EMF of 22V is for each battery?
 
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The load resistance is the resistance of the resistor that is added to the circuit. In this case, the total resistance is not the same as the load resistance.
 
So RL = ((1/R1) + (1/R2))^-1 is an incorrect statement?
 
Your equation RL = ((1/R1) + (1/R2))^-1 only equates the total (internal) resistance of the batteries. The load resistance is a separate load (resistor) in the circuit which is in series with the two batteries. R(total)=(total internal resistance)+(load resistance RL).
 
Circuit/Power

Howdy,
If I've got the right circuit in mind, you could use Thevenin's Theorem to find the thevenin equivalent circuit then determine I and P.

Peace out.

Fez07
 
Circuit/Power

Me again,
Forget my last comment. I was thinking of the wrong circuit. Use Superposition.
 
Don't recognize either of those, Fez07
 
Circuit/Power

Firstly, is this the circuit you have?
 

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