# Voltage vs. Current

By Jaxson

• Voltage

Voltage, electric potential difference, electric pressure or electric tension is the difference in electric potential between two points. The difference in electric potential between two points (i.e., voltage) in a static electric field is defined as the work needed per unit of charge to move a test charge between the two points. In the International System of Units, the derived unit for voltage is named volt. In SI units, work per unit charge is expressed as joules per coulomb, where 1 volt = 1 joule (of work) per 1 coulomb (of charge). The official SI definition for volt uses power and current, where 1 volt = 1 watt (of power) per 1 ampere (of current). This definition is equivalent to the more commonly used ‘joules per coulomb’. Voltage or electric potential difference is denoted symbolically by ∆V, but more often simply as V, for instance in the context of Ohm’s or Kirchhoff’s circuit laws.

Electric potential differences between points can be caused by electric charge, by electric current through a magnetic field, by time-varying magnetic fields, or some combination of these three. A voltmeter can be used to measure the voltage (or potential difference) between two points in a system; often a common reference potential such as the ground of the system is used as one of the points. A voltage may represent either a source of energy (electromotive force) or lost, used, or stored energy (potential drop).

Wikipedia
• Voltage (noun)

The difference in conductors or the earth.

“The voltage between the wires is too low to produce a spark.”

“Be careful when opening high-voltage equipment.”

• Current (noun)

The part of a fluid that moves continuously in a certain direction.

• Current (noun)

The time rate of flow of electric charge.

• Current (noun)

A tendency or a course of events.

Existing or occurring at the moment.

“current events;”

“current negotiations”

Generally accepted, used, practiced, or prevalent at the moment.

“current affairs;”

“current bills and coins;”

“current fashions”

Running or moving rapidly.

Wiktionary

belonging to the present time; happening or being used or done now

“keep abreast of current events”

“I started my current job in 2001”

in common or general use

“the other meaning of the word is still current”

• Current (noun)

a body of water or air moving in a definite direction, especially through a surrounding body of water or air in which there is less movement

“ocean currents”

• Current (noun)

a flow of electricity which results from the ordered directional movement of electrically charged particles

“this completes the circuit so that a current flows to the lamp”

“magnetic fields are produced by currents flowing in the cables”

• Current (noun)

a quantity representing the rate of flow of electric charge, usually measured in amperes

“at high currents there is wasteful power dissipation”

• Current (noun)

the general tendency or course of events or opinion

“the student movement formed a distinct current of protest”

Oxford Dictionary