Most devices large factory dynamos for example that are directly connected to the electrical grid operate on alternating current, and electrical outlets in homes and commercial areas supply alternating current as well. Devices that require direct current, like laptops, usually have an AC adapter that converts alternating current to direct current. Alternating current is the current of choice globally as it has many clear advantages compared to direct current.
For a full breakdown of differences between the two, see AC vs DC. Some advantages include: [6]. The University of Colorado has graciously allowed us to use the following Phet simulation that explores how alternating current works.
Fossil Fuels. Nuclear Fuels. Acid Rain. Climate Change. Climate Feedback. Ocean Acidification. To reduce the voltage of DC, is quite a bit more difficult. There are only a few ways to do this. The most efficient is to convert it to AC in some way. Even switching power supplies have a PWM controlled alternating voltage. It is also a lot harder to convert high voltage DC than a lower voltage. There are actually high voltage DC transmission lines. They are almost always used to isolate separate AC networks.
Most of them are used to connect different frequencies of AC. Others are used to isolate networks which may be out of phase with each-other. They can also be used to simplify the connection of remote generators.
DC lines can carry more power actually power lines do not carry power at all it is carried in the space around the wire as electromagenitic fields because a major limit of lines is the peak voltage they can carry before break down. AC spends a lot of time "off peak" but DC is always at its peak. Sign up to join this community. The best answers are voted up and rise to the top.
Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. How does AC travel through wires? Ask Question. Asked 9 years, 9 months ago. Active 9 years, 9 months ago. Viewed 9k times. C can travel miles and miles while D.
C can't? Since, from Ohm's law, So, I think the resistance would be the factor in case of D. C but how does A. C overcomes it? Community Bot 1. Sryia Sryia 2 2 silver badges 4 4 bronze badges.
Source: Public Domain. Both AC and DC describe types of current that flow in a circuit. Many sources of electricity, most notably electromechanical generators, produce AC current with voltages that alternate in polarity, reversing between positive and negative over time. An alternator can also be used to purposely generate AC current. In an alternator, a loop of wire is spun rapidly inside of a magnetic field.
This produces an electric current along the wire. As the wire spins and periodically enters a different magnetic polarity, the voltage and current alternate on the wire.
This current can change direction periodically, and the voltage in an AC circuit also periodically reverses because the current changes direction. AC comes in several forms, as long as the voltage and current are alternating. If an AC circuit is hooked up to an oscilloscope and its voltage is plotted over time, you are likely to see several different waveforms such as sine, square, and triangle — sine is the most common waveform and the AC in most mains-wired buildings have an oscillating voltage in the sine wave form.
AC is most commonly found in mains-wired buildings such as homes and offices. This is because generating and transporting an AC current across long distances is relatively easy.
At high voltages of over kV, less energy is lost in power transmission. At higher voltages, lower currents are produced, and lower currents generate less heat in the power line due to a lower level of resistance. This therefore means less energy lost as heat.
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