Difficulty: Medium
Correct Answer: -27.3 degrees
Explanation:
Introduction:
In a series RC circuit supplied by a sinusoidal source, the impedance has a resistive part R and a capacitive reactance Xc. The phase angle θ between the source voltage and the current indicates whether the circuit is more resistive (angle near 0) or more capacitive (negative angle). For capacitors, current leads voltage, so the net circuit angle is negative.
Given Data / Assumptions:
Concept / Approach:
The impedance angle for a series RC is θ = -arctan(Xc / R). Capacitive reactance is Xc = 1 / (2 * π * f * C). Negative sign indicates a capacitive circuit (current leads).
Step-by-Step Solution:
Verification / Alternative check:
If R were equal to Xc, θ would be -45 degrees. Here Xc < R, so |θ| must be smaller than 45 degrees, consistent with -27.3 degrees.
Why Other Options Are Wrong:
Common Pitfalls:
Final Answer:
-27.3 degrees
Discussion & Comments