Calculate Thevenin Equivalent Voltage

Thevenin Voltage Formula:

\[ V_{th} = V_{source} \times \frac{R2}{R1 + R2} \]

Thevenin Equivalent Voltage (V_th):

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1. What is Thevenin Equivalent Voltage?

The Thevenin equivalent voltage (V_th) is the open-circuit voltage at the terminals of a linear electrical network. It represents the voltage source in the Thevenin equivalent circuit, which simplifies complex networks into a single voltage source and series resistance.

2. How Does the Calculator Work?

The calculator uses the voltage divider formula:

\[ V_{th} = V_{source} \times \frac{R2}{R1 + R2} \]

Where:

\( V_{source} \) — Source voltage (V)
\( R1 \) — First resistor in the divider (Ω)
\( R2 \) — Second resistor in the divider (Ω)

Explanation: This formula calculates the voltage across R2 in a simple voltage divider circuit, which corresponds to the Thevenin equivalent voltage when looking into the divider from the output terminals.

3. Importance of Thevenin Voltage Calculation

Details: Thevenin equivalent circuits are fundamental in circuit analysis, allowing engineers to simplify complex networks for analysis and design. The Thevenin voltage is crucial for determining how a circuit will behave when connected to different loads.

4. Using the Calculator

Tips: Enter source voltage in volts, and both resistor values in ohms. All values must be valid (voltage ≥ 0, resistances > 0).

5. Frequently Asked Questions (FAQ)

Q1: What is Thevenin's theorem?
A: Thevenin's theorem states that any linear electrical network with voltage and current sources and resistances can be replaced by an equivalent circuit consisting of a single voltage source (V_th) in series with a single resistance (R_th).

Q2: When is the voltage divider formula applicable?
A: The voltage divider formula is applicable for two resistors in series connected across a voltage source, when no current is drawn from the output.

Q3: What are the limitations of this calculation?
A: This calculation assumes ideal resistors and a perfect voltage source. It doesn't account for source impedance, temperature effects, or non-linear components.

Q4: How does load affect the Thevenin voltage?
A: The Thevenin voltage is defined as the open-circuit voltage, so it remains unchanged regardless of the load connected to the circuit.

Q5: Can this be used for AC circuits?
A: For AC circuits with resistive elements only, the same formula applies. For reactive components, complex impedance must be used instead of resistance.