Which is equal to 500 milliwatts?

The metric prefix 'milli' stands for one one-thousandth (1/1000 or 10^-3). To convert a measurement from a 'milli' unit back to its base unit, you must divide the value by 1000. To apply this to 500 milliwatts, simply move the decimal point three places to the left, which is the equivalent of calculating 500 ÷ 1000. This calculation results in 0.5. Therefore, 500 milliwatts is exactly equal to 0.5 watts. Many incorrect options rely on bad decimal math. For example, moving the decimal point only two places gives 5 watts, while multiplying by 1000 instead of dividing gives a highly inflated 500,000 watts.