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Electric Current flows either in one Direction or keeps changing its Directions periodically. Hence, there are two ways of Current flow, namely; Alternating Current (AC) and Direct Current (DC). The major difference between AC and DC is that Current electricity flows gradually in one Direction in the Direct Current (DC). However, Current continuously varies its Direction from forward to backward and vice versa. Learn more about the points that distinguish between AC and DC.
What is an AC Current?
The term AC refers to Alternating Current in Physics, which is highly preferred electric power for office, household equipment, and more. The critical difference between Alternating Current and Direct Current lies in the Direction in which electric charges flow. In AC, electrons continuously change their Directions from forward to backward periodically.
The curve of an Alternating Current when drawn on a graph represents the sine waveform. The curved lines denote electric cycles that are measured per second. As compared to DC Current, it’s easy to generate and transport AC across large distances. Hence, Alternating Current is widely used in buildings, powerhouses, and more.
What is a DC Current?
DC refers to Direct Current in which there is no change in the Direction of Current flow. Hence, the major difference between AC and DC Current is the electric current flows only in One Direction in a stable voltage in DC Current. One of the major uses of DC is to charge batteries and supply power for electrical devices. In the DC circuit, electrons emerge from the negative side and move towards the positive side. The basic source of DC is produced by photovoltaic cells, batteries, or electrochemical cells.
The above image shows that Direct Current flows in one direction. The graph shows the proportionality between the magnitude of DC and time.
Anything that uses an AC adapter while plugging into a wall or that runs on a battery depends on Direct Current. Some of the examples of DC include flashlights, mobile phone batteries, electric vehicles, and more. By going through the difference between AC Current and DC Current, it’s easy to understand why AC is most referred to across several applications.
How Alternating Current is Converted into Direct Current?
There are several cases when there is a necessity to convert AC into DC. It’s because of the AC and DC difference that Direct Current is less preferred over long distances. To convert AC into DC, a power supply that consists of a transformer is required. Later it gets converted into Direct Current with the help of a rectifier. The conversion of AC into DC is beneficial to prevent the flow of Current from reversing. A filter used eradicated the Current pulsations in the rectifier output.
To sum up, the points of difference between AC and DC include:
Differentiate Between AC and DC Current
|
Points of Difference |
Alternating Current (AC) |
Direct Current (DC) |
|
Travelling Distance |
It’s safe to transfer Alternating Current over long distances and maintain electric power. It can transfer between two cities. |
From comparing AC and DC Current, it’s found that DC cannot travel for far distances. It’s because DC loses electric power. |
|
Electron Flow |
In AC, electrons keep switching their Direction from frontward to backward. |
Electrons only move in a forward Direction in a DC Motor. |
|
Frequency |
The frequency of the Alternating Current is generally between 50 to 60 Hz. Moreover, it’s frequency depends upon the country. |
The Direct Current has no or zero frequency. |
|
Source of Availability |
The source of availability for AC Current is AC generators. |
The source of availability for DC Current is either battery, electrochemical cell, or photovoltaic cell. |
|
Types |
Generally, AC Current is of sinusoidal type. Its other types can be triangular and square trapezoidal. |
The DC Current is of pure and pulsating form. |
|
Flowing Direction |
There is a change in the Direction of the Current electricity flow due to the rotating magnets. |
The Direct Current flows in a single direction due to steady magnetism. |
|
Applications |
From the AC Current and DC Current difference, it can be said that AC is capable of powering electric Motors used on washing machines, refrigerators, and so on. |
The Direct Current is preferably used in cellphones—flat-screen TVs, and so on. |
|
Loss of Energy |
As compared to DC, the loss of energy during the transmission in AC voltage is low. |
DC involves a high loss of energy and is hence not preferred when transformers are at a distance. |
Ohm’s Law
Ohm’s Law frames that the voltage across an electric conductor is Directly proportional to the Current flowing via it (provided all physical necessities and temperature remain constant). Ohm’s Law is useful only when the given temperature and the other physical factors stay constant. In certain components, expanding the Current raises the temperature. For Example- the filament of a light bulb, in which the temperature increases as the Current is increased. Ohm’s Law cannot be applied to such conditions because the Current is a variable here. The lightbulb filament breaks Ohm’s Law.
Faraday’s Law
Faraday’s Law or the Law of electromagnetic induction is the essential Law of electromagnetism, which allows to indicate how a magnetic field would interact with an electric circuit to generate an emf (electromotive force) which is also called electromagnetic induction.
Faraday’s Laws of Electromagnetic Induction consists of 2 Laws. They are-
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Faraday’s First Law of Electromagnetic Induction- Faraday’s First Law of Electromagnetic Induction states that an emf (electromotive force) is caused in the coil when the magnetic flux across the coil varies with time.
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Faraday’s Second Law of Electromagnetic Induction- Faraday’s Second Law of electromagnetic induction remarks that the induced emf (electromotive force) in a coil is equivalent to the rate of change of the flux linkage.