Question

Name and define unit for electric current.

Answer 1

Hint: Electric current is defined as the rate of flow of charge per unit time through a point or region. An electric current is said to exist when there is a net flow of electric charge through a region.

Complete step by step answer:
First we will know about the electric current, its properties and then we will know about its measuring units. Electric current is nothing but the rate of flow of electric charge per unit time through a region. Electric charge is carried by charged particles, so an electric current is a flow of charged particles. These charged particles can be either positively charged particles (protons or positive ions) or negatively charged particles (electrons). This electric current can be measured using an ammeter. Basically current is classified into two types: alternating current(AC) and direct current(DC). Alternating current is defined as the electric current that reverses its direction many times a second at regular intervals, typically used in power supplies whereas direct current is an electric current flowing in one direction only. It is measured in coulombs per second as from its definition it is clear that current is rate of flow of charge and coulomb is unit of charge. This can be given by,

$$i\quad =\quad \dfrac { dq }{ dt } $$ where i denotes electric current, q denotes charge, t denotes time.

The SI unit of electric current is Ampere. It is denoted by the letter A. Ampere is defined as one coulomb of charge moving past a point in one second. If there are electrons flowing through the frame in one second, then the electrical current flowing through it is ‘One Ampere.’ The unit Ampere is widely used within electrical and electronic technology along with the multipliers like milliamp (0.001A), microamp (0.000001A).

Note: Electric current is very essential in today’s lives. Even the basic appliances we use daily like television, digital clock, mobile phones require electricity to function. Hence, it is clear that our daily life is very much dependent on electric current. So, it is our responsibility to learn about electric current.