Updated: Dec 9, 2025 | Source: 2022-2026 Question Pool | Topic: T5B
T5B05T5B

Which is equal to 500 milliwatts?

Deep Dive: T5B05

The correct answer is B: 0.5 watts. 500 milliwatts equals 0.5 watts. The prefix 'milli-' means one-thousandth, so 1 milliwatt = 0.001 watts. To convert milliwatts to watts, divide by 1,000. 500 mW ÷ 1,000 = 0.5 W. This is a straightforward power unit conversion. Milliwatts (mW) are commonly used for small power levels (like receiver power consumption), while watts (W) are used for larger power levels (like transmitter output). Understanding these conversions is important for reading equipment specifications.

Why Other Answers Are Wrong

Option A: Incorrect. 0.02 watts equals 20 milliwatts, not 500 milliwatts. You're off by a factor of 25. Option C: Incorrect. 5 watts equals 5,000 milliwatts, not 500 milliwatts. You multiplied instead of dividing. Option D: Incorrect. 50 watts equals 50,000 milliwatts, way too large. You're off by a factor of 100.

Exam Tip

Milliwatts to watts = Divide by 1000. Remember: To convert milliwatts to watts, divide by 1,000. 500 mW ÷ 1000 = 0.5 W.

Memory Aid

**M**illiwatts **T**o **W**atts = **M**ove **T**hree **D**ecimal **P**laces **L**eft (think 'MTW = MTDPL' = Move Three Decimal Places Left, divide by 1000)

Real-World Example

Your handheld transceiver might consume 500 milliwatts (0.5 watts) when receiving. This is a very low power consumption, which is why handhelds can operate for many hours on a small battery. Understanding that 500 mW = 0.5 W helps you understand power consumption specifications and calculate battery life.

Source & Coverage

Question Pool: 2022-2026 Question Pool

Subelement: T5B

Reference: FCC Part 97.313

Key Concepts

Power conversion Milliwatts Watts Unit conversion

Verified Content

Question from the official FCC Technician Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the T5B topic.