Problem 52-6    Fonte:  Problem 12.15 - page 262 -    EDMINISTER, Joseph A. -    Livro: Circuitos Elétricos - Ed. McGraw Hill - 1971.

In the circuit shown in the Figure 52-06, the load Z_L is constituted by a variable resistance R_L. Determine the value of R_L for which the source delivers the maximum power to the load. Determine the value of this maximum power, P.

Solution of the Problem 52-6   

This problem meets the requirements of Case 1, seen in the Maximum Power Transfer Theorem that can be reviewed   click here!

Thus, the condition for maximum power transfer from the source to the load occurs when the following condition is satisfied:

Then, by doing the numerical substitution, we find:

Knowing the value of R_L we can calculate the value of the electric current that flows through the circuit. Like this:

Efetuando o cálculo:

Now we can calculate the maximum power, P, dissipated in the load.