## Main Difference – Watts vs. Volts

Watts and volts are both units used in measurements involving electric currents. The main difference between watts and volts is that watts are a unit for measuring power, whereas volts are a unit for measuring the electric potential difference.

## What is Volt

When an electric current flows around a circuit, electrons gain energy as they go through cells or generators, and they lose this energy as they go through loads that have resistance. **Electric potential** refers to the amount of electrical energy that a coulomb of electrons contains (a “coulomb” of electrons consists of 1.6×10^{19} electrons). The volt is the SI unit for measuring electric potential. The unit is named after the Italian scientist Alessandro Volta (1745–1827), who invented the voltaic cell. The symbol for volts is V.

## What is Watt

Watts measure **electric** **power**. Power measures the amount of energy that is transferred per unit time. If a current flows through two points in a circuit that have a potential difference of between them, then the total number of charge that flows between the two points in a time is (in coulombs). Since each coulomb of charge loses an energy as it flows between the two points, the *total* energy dissipated is . Then, the amount of energy dissipated *per unit time*, i.e. the **power dissipated**, is given by:

Watts are the SI unit for measuring electric power. Watts are named after the Scottish Engineer James Watt (1736–1819), the inventor of the Watt steam engine. The symbol for watts is W.

## Base Units for Volts and Watts

Voltage is a quantity of energy divided by a quantity of charge. Energy (work) is a product of force and distance. At the same time, charge is a product of current and time. So, **in terms of units**,

Since force is a product of mass and acceleration,

As we have seen earlier, power can be written as a product of potential difference and current. So, the base units of watts is:

## Difference Between Watts and Volts

**Watts** are a unit for measuring electric power, whereas **volts** are a unit for measuring electric potential.

The base unit for **watts** is kg m^{2} s^{-3}, whereas the base unit for **volts** is kg m^{2} A^{-1} s^{-3}.

Image Courtesy:

“Alessandro Giuseppe Antonio Anastasio Volta”, author unknown [Public Domain], via Wikimedia Commons

“James Watt statue” by DncnH (Own work) [CC BY-SA 2.0], via flickr