Question

What is maximum power transfer in equivalent circuit?

Answer 1

The Maximum Power Transfer Theorem states that in an electrical circuit, maximum power is delivered to the load when the load resistance (\( R_L \)) is equal to the source resistance (\( R_{source} \)) seen from the load.

To break it down:

1. Source Resistance: This is the resistance of the source or the part of the circuit that is supplying power.
   

1. Load Resistance: This is the resistance of the component or device you are trying to power (e.g., a motor, lamp, or resistor).
   

In an equivalent circuit:

1. The source is often represented as an ideal voltage source (V) in series with a resistance (\( R_{source} \)).
   

1. The load is represented as a resistor (\( R_L \)) connected to the voltage source.
   

For maximum power to be transferred to the load, the following condition must be met:
\[ R_L = R_{source} \]

Why is this important?

1. If the load resistance is too high or too low compared to the source resistance, the power transferred to the load will be less.
   

1. When \( R_L \) is equal to \( R_{source} \), the power delivered to the load is maximized.
   

Formula for Maximum Power:

When the load resistance equals the source resistance, the maximum power \( P_{max} \) delivered to the load can be found using this formula:
\[
P_{max} = \frac{V^2}{4 R_{source}}
\]
where \( V \) is the voltage supplied by the source, and \( R_{source} \) is the source resistance.

This condition ensures efficient power transfer in many practical applications, like in audio systems, wireless power systems, and communication circuits.