Question

What are the practical applications of the maximum power transfer theorem?

Answer 1

Maximum power transfer ensures that a load receives the maximum power that can be delivered to it. The theorem states that, to obtain maximum external power from a source with a finite internal resistance, the resistance of the load must equal the resistance of the source as viewed from its output terminals.

Complete step-by-step solution:
Maximum Power Transfer occurs when the resistive value of the load is equal in value to that of the voltage source's internal resistance allowing maximum power to be supplied.
Applications:
It’s used in solar cell applications, adjusting the electrical load on the cell to obtain maximum output power.
In radio communication, to transmit energy from your transmitter into the antenna efficiently. “Maximum power transfer takes place when the load impedance is equal to the complex conjugate of the source impedance.”
In car engines, the power delivered to the starter motor of the car will depend upon the effective resistance of the motor and the internal resistance of the battery. If the two resistances are equal, maximum power will be transferred to the motor to turn to the engine.
It also helps in making a circuit having maximum power dissipation correctly at the load of resistance.

Note: Also the condition of maximum power transfer does not result in maximum efficiency. The efficiency is only 50% when maximum power transfer is achieved, but approaches 100% as the load resistance approaches infinity, though the total power level tends towards zero. Efficiency also approaches 100% if the source resistance approaches zero, and 0% if the load resistance approaches zero.