Alternating current ac alternating current describes the flow of charge that changes direction periodically.
Ac power supply graph.
As the name implies it flows first in one direction and then the other.
P avg vi cosφ.
Mains electricity by country includes a list of countries and territories with the plugs voltages and frequencies they commonly use for providing electrical power to low voltage appliances equipment and lighting typically found in homes and offices.
The power that was actually used by the load i e.
As in the case with dc power the instantaneous electric power in an ac circuit is given by p vi but these quantities are continuously varying.
As a result the voltage level also reverses along with the current.
Where φ is the phase angle between the current and the voltage and where v and i are understood to be the effective or rms values.
What is alternating current ac.
Alternating current ac is different to direct current.
Ac supply main variations the maximum variations in ac supply mains is give or take 6 of its rated value.
The output voltage changes by a great value due to the huge change in the current drawn from the supply.
The term rms stands for root mean squared.
When an alternator produces ac voltage the voltage switches polarity over time but does so in a very particular manner when graphed over time the wave traced by this voltage of alternating polarity from an alternator takes on a distinct shape known as a sine wave.
Referring to the graph above the positive bits are power going to the load from the supply and the negative bits are power going back to the supply from the load.
For industrial machinery see industrial and multiphase power plugs and sockets some countries have more than one voltage available.
Therefore the ac power changes with time but the dc power does not.
In our tutorial about the ac waveform we looked briefly at the rms voltage value of a sinusoidal waveform and said that this rms value gives the same heating effect as an equivalent dc power and in this tutorial we will expand on this theory a little more by looking at rms voltages and currents in more detail.
Alternating current is the form in which electric power is delivered to businesses and residences and it is the form of electrical energy that consumers typically use when they plug kitchen.
The instantaneous values of current and voltage changes over time in ac power sources while in dc sources they remain constant.
Ac power vs dc power.
Graph explaining alternating current.
Almost always the desired power in an ac circuit is the average power which is given by.
But this value may go higher in some.
The graph above shows the current waveform varying as a sine wave with the current first moving in one direction and then the other.
Power delivered from an ac source is known as ac power and power delivered from dc sources are known as dc power.
This is mainly due to the high internal resistance of the power supply 30 ohms.
Graph of ac voltage over time the sine wave.
Alternating current ac is an electric current which periodically reverses direction and changes its magnitude continuously with time in contrast to direct current dc which flows only in one direction.
