Which unit is used to measure the difference of potential between two points?

• A. Amperes (amps)
• B. Ohms
• C. Watt
• D. Volts

Answer: (D)

Voltage is the potential difference between two points. The unit for this quantity is the volt, which equals one joule per coulomb of charge. This measures how much energy per unit charge is available to push charges from one point to another. In contrast, current is measured in amperes (the rate of charge flow), resistance in ohms (opposition to flow), and power in watts (rate of energy transfer). Therefore, the unit used to measure the difference of potential between two points is the volt.