FCC Question Pool Review

Technician Class (Element 2) • 2022-2026

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Question T5B05

From subelement T5 - T5B

T5B05
Answer: B

Which is equal to 500 milliwatts?

A0.02 watts
B0.5 watts
C5 watts
D50 watts

Why is this correct?

Converting milliwatts to watts requires dividing by 1,000 since 'milli' means one-thousandth. So 500 milliwatts ÷ 1,000 = 0.5 watts. Choice A (0.02) would be 20 milliwatts. Choice C (5 watts) would be 5,000 milliwatts. Choice D (50 watts) would be 50,000 milliwatts. The key is remembering that milli prefix means divide by 1,000 when converting to the base unit.

Memory tip

For metric prefix conversions, memorize that milli always means ÷1,000 and kilo means ×1,000. This pattern works across all electrical units: milliamps to amps, milliwatts to watts, kilohertz to hertz. The decimal point simply moves three places.

Learn more

Power measurements are critical in amateur radio for managing RF exposure limits and ensuring proper equipment operation. Many handheld transceivers operate in the milliwatt to low-watt range, while base stations may use hundreds of watts. Understanding these conversions helps you select appropriate equipment for your intended coverage area and comply with station power limitations specified in Part 97.

Think about it

Why do you think amateur radio equipment specifications often use different power units (milliwatts vs watts) depending on the device type?