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Why AC is a sine wave?
But in basic circuit analysis and AC signal analysis, we tend to use sine waves because they are the easiest to generate (as compared to square/ramp signals) as well as the easiest to analyze mathematically (all our calculus tools work wonderfully for curves like the sine, but tend to be more inconvenient around things …
Is current a sine wave?
The number of times an alternating current repeats a full cycle per second is the frequency and the maximum the current reaches in either direction is its amplitude. The waveform of an alternating current power circuit is a sine wave.
Which is not a sine wave?
A non-sinusoidal waveform is typically a periodic oscillation but is neither of these. Some examples are triangle waves, rectangle waves, square waves, trapezoid waves and saw tooth waves.
Is a sine wave AC or DC?
An AC supply is suitable for powering some devices such as lamps and heaters but almost all electronic circuits require a steady DC supply (see below). This shape is called a sine wave. This triangular signal is AC because it changes between positive (+) and negative (-).
Can we produce AC voltage?
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. This produces an electric current along the wire.
What creates a sine wave?
Generation of Voltage Initially the coil is perpendicular to the magnetic field generating maximum voltage. As the coil rotates the voltage decreases according to the sine of the angle until the conductor is parallel to the magnetic field. For each revolution a complete sine wave is generated.
Is AC always a sine wave?
While alternating currents produced by rotating machinery will naturally be produced in a sinusoidal wave, AC is not defined as sinusoidal; it is entirely possible to generate other non-sinusoidal alternating currents.
What does a sine curve look like?
The shape of the sine curve is the same for each full rotation of the angle and so the function is called ‘periodic’. The period of the function is 360° or 2π radians. You can rotate the point as many times as you like. This means you can find the sine of any angle, no matter how large.
Why DC is not used in homes?
Direct current is not used at home because for the same value of the voltage, DC is more lethal than AC since direct current does not go through zero. Electrolytic corrosion is more an issue with direct current.
What are the characteristics of an AC sine wave?
Some of the important electrical characteristics and terms used when referring to AC sine wave voltages or currents are cycle, period, and frequency. One cycle is one complete wave of alter¬ nating voltage or current (Figure 21- 9).
How is the sine wave of alternating current determined?
The answer is actually very elegant. Start by remembering from trigonometry how the sine is defined and it’s relation to circular motion – the unit circle: Keep in mind that the flow of current is determined by voltage. As the voltage changes, the flow reverses. The direction of the push – pull is determined by the voltage at the source.
How is the peak value of a sine wave determined?
Since an alternating current is produced by an alternating voltage, the same rule applies in terms of its effective value. The effective value of a volt¬ age sine wave is equal to 0.707 times its peak value. This equation can be transposed so that the peak value of a sine wave can be determined if its effective value is known.
Which is the RMS value for a sine wave?
The RMS or ROOT MEAN SQUARED value is the value of the equivalent direct (non varying) voltage or current which would provide the same energy to a circuit as the sine wave measured. That is, if an AC sine wave has a RMS value of 240 volts, it will provide the same energy to a circuit as a DC supply of 240 volts.