BASIC ELECTRONICS - OD1633 - LESSON 1/TASK 2
Given:
Es = 30 volts
IT = 15 amps
The equivalent resistance of the circuit shown in figure 50 on the previous
page is smaller than either of the two resistors (R1, R2).
A point to
remember is that the equivalent resistance of a parallel circuit is always
less than the resistance of any branch.
Equivalent resistance can be found if you know the individual resistance
values and the source voltage. By calculating each branch current, adding
the branch currents to calculate total current, and dividing the source
voltage by the total current, the total can be found. This method, while
effective, is somewhat lengthy.
A quicker method of finding equivalent
resistance is to use the general formula for resistors in parallel:
If you apply the general formula to the circuit shown in figure 50, you will
get the same value for equivalent resistance (2 Ohms) as was obtained in the
previous calculation that used source voltage and total current.
Given:
R1 = 3 Ohms
R2 = 6 Ohms
81
Previous Page
