Amateur ExtraE5C06
What does the impedance 50 - j25 ohms represent?
B
Answer
Electrical principles and calculations
Type
A
50 ohms resistance in series with 25 ohms inductive reactance
B
50 ohms resistance in series with 25 ohms capacitive reactance
C
25 ohms resistance in series with 50 ohms inductive reactance
D
25 ohms resistance in series with 50 ohms capacitive reactance
Answer Notes
In rectangular coordinates, impedance is written in the format R + jX, where 'R' is the real part representing pure resistance, and 'jX' is the imaginary part representing reactance. In the expression 50 - j25 ohms, the real part is 50, indicating 50 ohms of series resistance.
The 'j' operator denotes the reactance type. A positive 'j' indicates inductive reactance, while a negative 'j' indicates capacitive reactance. Since this value has a negative sign (-j25), it corresponds to 25 ohms of capacitive reactance in series with the resistance.
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Where is the impedance of a pure resistance plotted on rectangular coordinates?