Difficulty: Easy
Correct Answer: 8.48∠45°
Explanation:
Introduction / Context:
Converting between rectangular and polar forms lets us pick the most convenient representation for circuit computations. Equal real and imaginary parts indicate a 45° angle in the first quadrant for positive values.
Given Data / Assumptions:
Concept / Approach:
Calculate magnitude and angle directly. Because a = b > 0, the angle should be 45°, serving as a quick sanity check.
Step-by-Step Solution:
Verification / Alternative check:
Back-conversion: a = M cosθ ≈ 8.48 * 0.707 ≈ 6; b = M sinθ ≈ 8.48 * 0.707 ≈ 6.
Why Other Options Are Wrong:
6∠45° has correct angle but wrong magnitude. 8.48∠90° has correct magnitude but wrong angle. 36∠45° has magnitude squared error (not how polar magnitude is defined).
Common Pitfalls:
Confusing RMS/peak ideas with complex magnitude; forgetting that equal components imply 45° in quadrant I.
Final Answer:
8.48∠45°
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