# Current, Voltage, Power

## What is current?

There are two kinds of electricity. One is static (i.e. static electricity) and the other is dynamic (i.e. current). Current is the flow of electrons. The intensity of current is determined by the rate of electron flow per second. Ampere (abbreviated as A) is the unit for measuring the intensity of current.

## What is voltage?

Voltage is the force that makes the current flow in a circuit. Voltage can affect the current. The higher the voltage, the greater the flow of current, and the stronger the electrical power created. A drop in voltage will result in a corresponding decrease in current and electrical power. Voltage is measured in Volts (abbreviated as V). At present, the voltages in Hong Kong are 220V (single phase) and 380V (three phase).

## What is power?

Power refers to the amount of electrical energy consumed by an electrical appliance within a certain time. Power is measured in Watts (abbreviated as W). The greater the power, the more energy consumed by the appliance per second.

The measuring units for current, voltage and power are named after famous scientists André-Marie Ampère, Alessandro Volta and James Watt for their contribution to science.
4 December 2020