Internal resistance circuit problem

• Sarlizwx
In summary: Yes, the circuit shown in the diagram is correct.In summary, the conversation discusses a circuit with two identical batteries in parallel and a load resistance of 35 Ohms. The question at hand is to find the power transferred to the load resistor. The conversation also touches on Thevenin's Theorem and Superposition as potential methods to solve the problem. The correct equation for the load resistance is R(total) = (total internal resistance) + (load resistance).

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?

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?

Attachments

• Circuit-Power.doc
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1. What is internal resistance in a circuit?

Internal resistance in a circuit refers to the inherent resistance present within a power source, such as a battery. It is caused by the materials and construction of the power source and can affect the overall performance and efficiency of the circuit.

2. How does internal resistance affect a circuit?

Internal resistance can cause a voltage drop within the circuit, resulting in a decrease in the amount of current that can flow through the circuit. This can lead to a decrease in the overall power output of the circuit and can also cause the power source to heat up.

3. How can internal resistance be measured?

Internal resistance can be measured by using a multimeter to measure the voltage drop across the power source and the current flowing through the circuit. The internal resistance can then be calculated using Ohm's law (R = V/I).

4. What factors can affect the internal resistance of a circuit?

The internal resistance of a circuit can be affected by factors such as the type and quality of the power source, the temperature, and the length and thickness of the wires used in the circuit. The internal resistance may also vary depending on the current and voltage levels in the circuit.

5. How can internal resistance be minimized?

Internal resistance can be minimized by using high-quality power sources with low internal resistance. Keeping the power source at a stable temperature and using shorter and thicker wires can also help reduce the internal resistance in a circuit. Additionally, using a voltage regulator can help maintain a constant voltage level and reduce the effects of internal resistance.