500 mV is equal to how many volts?

• A. 5 V
• B. 0.05 V
• C. 0.5 V
• D. 50 V

Answer: (C)

The milli prefix means one-thousandth of a volt, so to convert millivolts to volts you divide by 1000. Therefore 500 millivolts equals 0.5 volts (500 ÷ 1000 = 0.5). In context, 5 volts would be 5000 millivolts, 0.05 volts is 50 millivolts, and 50 volts is 50,000 millivolts, so 0.5 volts is the correct conversion.