What is the unit of electric pressure or electromotive force that would produce a current of 1 ampere through a resistance of 1 ohm?

What is the unit of electric pressure or electromotive force that would produce a current of 1 ampere through a resistance of 1 ohm?

• A. Watt
• B. Ampere
• C. Volt
• D. Ohm

Answer: (C)

Voltage is the electric pressure that pushes current through a circuit. Ohm’s Law ties these quantities together as V = I × R. To get a current of 1 ampere through a resistance of 1 ohm, you multiply I by R: 1 A × 1 Ω = 1 V. So the required unit is the volt, which is the unit of electromotive force or electric pressure. Watt is a unit of power (voltage times current), not a pressure; Ampere is the unit of current, not the driving force; Ohm is the unit of resistance, not the pressure that drives current.

Voltage is the electric pressure that pushes current through a circuit. Ohm’s Law ties these quantities together as V = I × R. To get a current of 1 ampere through a resistance of 1 ohm, you multiply I by R: 1 A × 1 Ω = 1 V. So the required unit is the volt, which is the unit of electromotive force or electric pressure.

Watt is a unit of power (voltage times current), not a pressure; Ampere is the unit of current, not the driving force; Ohm is the unit of resistance, not the pressure that drives current.