Which point on Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and a 19-picofarad capacitor at 21.200 MHz?

Q: Which point on Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and a 19-picofarad capacitor at 21.200 MHz?

The correct answer is A: Point 1. The correct answer is A: Point 1. Which point on Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and a 19-picofarad capacitor at 21.200 MHz is Point 1. At 21.200 MHz, XC = 1/(2πfC) ≈ 400Ω. Impedance ≈ 300 - j400, which corresponds to Point 1. For amateur radio operators, this is important for circuit analysis. Understanding this helps when reading impedance charts.

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Deep Dive: E5C12

The correct answer is A: Point 1. Which point on Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and a 19-picofarad capacitor at 21.200 MHz is Point 1. At 21.200 MHz, XC = 1/(2πfC) ≈ 400Ω. Impedance ≈ 300 - j400, which corresponds to Point 1. For amateur radio operators, this is important for circuit analysis. Understanding this helps when reading impedance charts.

Why Other Answers Are Wrong

Option B (Point 3): Incorrect. Point 3 doesn't represent this impedance - Point 1 does. Point 3 is wrong. Option C (Point 7): Incorrect. Point 7 doesn't represent this impedance - Point 1 does. Point 7 is wrong. Option D (Point 8): Incorrect. Point 8 doesn't represent this impedance - Point 1 does. Point 8 is wrong.

Exam Tip

300Ω resistor + 19pF capacitor at 21.200 MHz = Point 1 on Figure E5-1. Think '3'00Ω + '1'9pF at '2'1.200 MHz = 'P'oint '1'. At 21.200 MHz, XC ≈ 400Ω, impedance ≈ 300 - j400, Point 1. Not Point 3, not Point 7, not Point 8 - just Point 1.

Memory Aid

300Ω resistor + 19pF capacitor at 21.200 MHz = Point 1 on Figure E5-1. Think '3'00Ω + '1'9pF = 'P'oint '1'. At 21.200 MHz, XC ≈ 400Ω, impedance ≈ 300 - j400, Point 1. Important for circuit analysis.

Real-World Example

A series circuit with 300-ohm resistor and 19-picofarad capacitor at 21.200 MHz: At 21.200 MHz, XC = 1/(2π×21.200×10^6×19×10^-12) ≈ 400Ω. Impedance ≈ 300 - j400 ohms. On Figure E5-1, this corresponds to Point 1. This is the point - Point 1.

Source & Coverage

Question Pool: 2024-2028 Question Pool

Subelement: E5C

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

Key Concepts

Figure E5-1 Series circuit 300-ohm resistor 19-picofarad capacitor 21.200 MHz Point 1

Official Pool Source

Question text and answer key are synchronized with the current NCVEC Extra Class pool and mapped to the E5C topic.