Question

In a network maximum power transfer occurs when

• A. \( R_{Th} = -R_L \)
• B. \( \frac{R_{Th}}{R_L} = 0 \)
• C. \( R_{Th} = R_L \)
• D. \( R_{Th} + R_L = 1 \)

Hint:

The Maximum Power Transfer Theorem is a critical concept in circuit design, especially for power amplifiers and communication systems. Remember the condition: maximum power is transferred when the load resistance ($R_L$) is equal to the Thevenin equivalent resistance ($R_{Th}$) of the source network. Also, know that while power transfer is maximized, the efficiency at this point is only 50\%, as an equal amount of power is dissipated within the source's internal resistance.

Answer 1

The Correct Option is C

The question asks about the condition for maximum power transfer in a network.

1. Understanding the Concepts:

- Maximum Power Transfer Theorem: In a linear, bilateral, DC circuit, maximum power is transferred from a source to a load when the load resistance (R_L) is equal to the Thevenin resistance (R_Th) of the network as seen from the load terminals. In an AC circuit, the load impedance should be equal to the complex conjugate of the Thevenin impedance. 
- Thevenin Resistance (R_Th): The equivalent resistance of a circuit as seen from two terminals. 
- Load Resistance (R_L): The resistance of the load connected to the circuit.

2. Analyzing the Options:

The condition for maximum power transfer is that the load resistance is equal to the Thevenin resistance.

Final Answer:

In a network, maximum power transfer occurs when \( R_{Th} = R_L \).