What is a phasor quantity?

What is a phasor quantity?

A phasor is a rotating vector representing a quantity, such as an alternating current or voltage, that varies sinusoidally. A phasor is a rotating vector representing a quantity, such as an alternating current or voltage, that varies sinusoidally.

Which is correct for a phasor quantity?

A Phasor Diagram can be used to represent two or more stationary sinusoidal quantities at any instant in time. All phasors are drawn rotating in an anticlockwise direction. All the phasors ahead of the reference phasor are said to be leading while all the phasors behind the reference phasor are said to be lagging.

Is phasor a time dependent quantity?

Phasors are complex quantities used to partially represent real quantities that vary sinusoidally in time and perhaps in space. All phasors are time-independent.

What is difference between phasor and vector?

Although the both the terms vectors and phasors are used to describe a rotating line that itself has both magnitude and direction, the main difference between the two is that a vectors magnitude is the “peak value” of the sinusoid while a phasors magnitude is the “rms value” of the sinusoid.

Is phasor a vector?

In physics and engineering, a phasor (a portmanteau of phase vector), is a complex number representing a sinusoidal function whose amplitude (A), angular frequency (ω), and initial phase (θ) are time-invariant.

What is the phasor of an alternating quantity?

Such a rotating line is called the phasor. Consider a line OA (or phasor as it is called) representing to scale the maximum value of an alternating quantity, say emf i.e., OA = E max and rotating in counter-clockwise direction at an angular velocity ω radians/second about the point O, as shown in Fig. 3.30.

Which is the reference phasor for a series circuit?

For series circuits, in which the current is common to all parts of the circuit, the current phasor is usually taken as reference phasor for other phasors in the same diagram and drawn on horizontal line.

How is a phasor used to represent a sinusoidal quantity?

For solution of ac problems it is advantageous to represent a sinusoidal quantity (voltage or current) by a line of definite length rotating in counter­clockwise direction with the same angular velocity as that of the sinusoidal quantity. Such a rotating line is called the phasor.

Is the length of phasor equal to the RMS value?

Since there is definite relation between maximum value and rms value (E max = n√2 E rms ), the length of phasor OA can be taken equal to rms value if desired. But it should be noted that in such cases, the projection of the rotating phasor on the vertical axis will not give the instantaneous value of that alternating quantity.