Examples of Electric Current
We explain that what are the examples of electric current? with definition and battery in detail to better understanding…Lets Read Physics… examples of electric current
Electric current examples of electric current
The Electricity is the speed of the flow of electric charge somewhere in space. Most of the applications of electricity are oriented to electric currents.
Electric currents are classified into direct or direct current and alternating current .
For example, a lamp battery supplies current to a bulb filament when the switch is turned to the on position.
A wide variety of household appliances run on alternating current . In these common cases, the charge flow takes place in a conductive material, such as copper wire. However, currents may exist outside the conductor. For example, the electron beam in a television kinescope constitutes a current.
Battery examples of electric current
The Battery is a source of direct current . It was invented by Alessandro Volta in 1800, and it was one of the most important practical discoveries in science. This invention represents the foundation of a wide spectrum of subsequent developments in electrical technology.
Even when electrical phenomena were known before 1800, electrical machines of that time were limited to devices that produced static charge and large potential differences through friction. Such machines were capable of producing large sparks, but their practical value was quite limited.
During his research, Volta recognized that contact between two metals requires an aqueous conductor to obtain an appreciable effect. It also showed that certain pairs of metals produced a greater effect than others.
Volta then proceeded to invent a continuous source of electricity, the first battery . His original device, called a voltaic pile , consists of alternating silver and zinc plates. Adjacent plates were separated by a cloth soaked in dilute acid or saline solution.
The structure of the plates produces a Continuous Potential Difference between the two ends, with an excess of positive charge at the end of the silver and an excess of negative charge at the end of the zinc.
In effect, the cell was an energy converter, where internal chemical energy was converted into electrical potential energy. Although this battery produced a very small potential compared to that produced by frictional electrostatic machines, it was capable of giving a large electrical charge and thus proved to be of great practical importance.
These early sources were very important to the experiments because they produced an almost constant potential difference.
Whenever electric charges of the same sign are in motion , a current is said to exist . To define current more precisely, it must be assumed that charges move perpendicular to a surface area .
This area could be the cross section of a wire. The current is the speed with which the charge flows through that surface .
If ΔQ is the amount of charge that passes through this area in a time Δt, the average current I p is equal to the ratio of the charge in the time interval: examples of electric current
I p = ΔQ / Δt
If the speed with which the charge flows varies with time, the current also varies with time and the Instantaneous Current, I, is defined .
The SI unit of current is the Ampere (A) , where
1 A = 1 C / s
That is, 1 Ampere of current equals 1 Coulomb of charge passing through the surface in 1 second . In practice, smaller units of current are often used, such as the milliampere (1 mA = 10 -3 A) and the microampere (1 μA = 10 -6 A).
When charges flow across the surface, they can be positive, negative, or both. By convention, the direction of the current is chosen as the direction in which positive charges flow.
In a conductor like copper , the current is due to the movement of negatively charged electrons. Therefore, when we talk about current in an ordinary conductor, such as copper wire, the direction of the current will be opposite to the direction of the flow of electrons. examples of electric current
On the other hand, if one considers a beam of positively charged protons in an accelerator, the current is in the direction of the motion of the protons. In some cases, the current is the result of the flow of both positive and negative charges. This occurs, for example, in semiconductors and electrolytes.
It is common to refer to the movement of charges (positive or negative) as the movement of charge carriers .
In a conductor, free electrons travel at a speed close to that of light. Thus, when the light igniter is activated, the message for the electrons to start moving through the wire reaches them with a speed of approximately 10 8 m / s.
Examples of Electric Current
Computers are powered by electricity to start working.
The bulbs receive electrical current so that their filament lights up.
Household appliances work with a 110V potential difference electric current.
Office appliances and small laboratories work with a 220V potential difference electric current.
Industrial appliances operating on a large scale are powered by a 440V potential difference electric current.
Copiers, printers, and scanners are powered by electrical current.
Speakers and other audio devices receive electrical current for their operation.
Treadmills, which are gym equipment with a moving band, require electrical current.
Cell phone batteries are recharged with electrical current.
Lighting fixtures such as reflectors are powered by electrical current to achieve intense brightness.