Updated: Dec 9, 2025 | Source: 2024-2028 Question Pool | Topic: E5C
E5C03E5C

Which of the following represents a pure inductive reactance in polar coordinates?

Deep Dive: E5C03

The correct answer is C: A positive 90 degree phase angle. Which of the following represents a pure inductive reactance in polar coordinates is a positive 90 degree phase angle. Inductive reactance has +90° phase angle. For amateur radio operators, this is important for circuit theory. Understanding this helps when working with impedance.

Why Other Answers Are Wrong

Option A: Incorrect. Positive 45 degree phase angle isn't pure inductive - pure inductive is +90°. 45° isn't correct. Option B: Incorrect. Negative 45 degree phase angle isn't pure inductive - pure inductive is +90°. -45° isn't correct. Option D: Incorrect. Negative 90 degree phase angle is capacitive, not inductive - inductive is +90°. -90° is capacitive.

Exam Tip

Pure inductive reactance in polar = positive 90 degree phase angle. Think 'I'nductive = '+9'0° phase angle. Inductive reactance has +90° phase angle. Not 45°, not -45°, not -90° (capacitive) - just +90°.

Memory Aid

Pure inductive reactance in polar = positive 90 degree phase angle. Think 'I'nductive = '+9'0°. Inductive reactance has +90° phase angle. Important for circuit theory.

Real-World Example

Pure inductive reactance in polar coordinates: It's represented by a positive 90 degree phase angle. For example, 100∠90° represents 100 ohms of inductive reactance. This is the representation - positive 90° phase angle.

Source & Coverage

Question Pool: 2024-2028 Question Pool

Subelement: E5C

Reference: 2024-2028 Question Pool · E5 - Electrical Principles

Key Concepts

Pure inductive reactance Polar coordinates Positive 90 degree phase angle Impedance notation

Verified Content

Question from the official FCC Extra Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the E5C topic.