How much real power is consumed in a circuit consisting of a 100-ohm resistor in series with a 100-ohm inductive reactance drawing 1 ampere?
The correct answer is B: 100 watts. How much real power is consumed in a circuit consisting of a 100-ohm resistor in series with a 100-ohm inductive reactance drawing 1 ampere is 100 watts. Real power = I²R = 1² × 100 = 100 watts. Only resistance consumes real power. For amateur radio operators, this is important for power calculations. Understanding this helps when calculating power.
Exam Tip
Real power = I²R (only resistance consumes real power). Think 'R'eal 'P'ower = 'I'²'R'. Real power = 1² × 100 = 100 watts. Not 70.7W, not 141.4W, not 200W - just 100 watts.
Memory Aid
"Real power = I²R (only resistance consumes real power). Think 'R'eal 'P'ower = '1'00 watts. Real power = 1² × 100 = 100 watts. Important for power calculations."
Real-World Application
A circuit with 100-ohm resistor and 100-ohm inductive reactance drawing 1 ampere: Real power = I²R = 1² × 100 = 100 watts. Only the resistance consumes real power; the reactance doesn't. This is the real power - 100 watts.
Key Concepts
Why Other Options Are Wrong
Option A (70.7 watts): Incorrect. 70.7 watts is too low - real power = I²R = 1² × 100 = 100 watts. 70.7 watts is wrong.
Option C (141.4 watts): Incorrect. 141.4 watts is too high - real power = I²R = 1² × 100 = 100 watts. 141.4 watts is wrong.
Option D (200 watts): Incorrect. 200 watts is too high - real power = I²R = 1² × 100 = 100 watts. 200 watts is wrong.
题目解析
The correct answer is B: 100 watts. How much real power is consumed in a circuit consisting of a 100-ohm resistor in series with a 100-ohm inductive reactance drawing 1 ampere is 100 watts. Real power = I²R = 1² × 100 = 100 watts. Only resistance consumes real power. For amateur radio operators, this is important for power calculations. Understanding this helps when calculating power.
考试技巧
Real power = I²R (only resistance consumes real power). Think 'R'eal 'P'ower = 'I'²'R'. Real power = 1² × 100 = 100 watts. Not 70.7W, not 141.4W, not 200W - just 100 watts.
记忆口诀
Real power = I²R (only resistance consumes real power). Think 'R'eal 'P'ower = '1'00 watts. Real power = 1² × 100 = 100 watts. Important for power calculations.
实际应用示例
A circuit with 100-ohm resistor and 100-ohm inductive reactance drawing 1 ampere: Real power = I²R = 1² × 100 = 100 watts. Only the resistance consumes real power; the reactance doesn't. This is the real power - 100 watts.
错误选项分析
Option A (70.7 watts): Incorrect. 70.7 watts is too low - real power = I²R = 1² × 100 = 100 watts. 70.7 watts is wrong. Option C (141.4 watts): Incorrect. 141.4 watts is too high - real power = I²R = 1² × 100 = 100 watts. 141.4 watts is wrong. Option D (200 watts): Incorrect. 200 watts is too high - real power = I²R = 1² × 100 = 100 watts. 200 watts is wrong.
知识点
Real power, Circuit, 100-ohm resistor, 100-ohm inductive reactance, 1 ampere, 100 watts
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.