Which is equal to 500 milliwatts?

To understand why 500 milliwatts is equal to 0.5 watts, it's essential to recognize the relationship between milliwatts and watts in the metric system.

1 watt is defined as 1,000 milliwatts. Therefore, to convert milliwatts into watts, you divide the number of milliwatts by 1,000.

So, in this case:

500 milliwatts divided by 1,000 equals 0.5 watts.

This means that when you see the measurement of 500 milliwatts, it equates to 0.5 watts, confirming that this is indeed the correct answer. The other options represent values that would either be too low or too high compared to the conversion from milliwatts to watts, allowing us to rule them out.