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## Main Question or Discussion Point

I'm sure my question is very simple to most of u guys. But I have the following confusion.

Let's say we have an AC voltage source in a circuit. In rectangular form it's phasor form is

v= -4 - 16 j .

I want to write this phasor in polar form. Well, The phasor is in 3rd quadrant of complex plane.

It's magnitude comes out to be 16.49

For phase angle,

[tex]\phi[/tex] = arctan (-16/-4) = 75.96◦

To shift 75.96 degrees from 1st quadrant to 3rd quadrant I can approach in 2 ways. like

[tex]\phi[/tex] = 75.96+ 180 = 255.96◦

or,

[tex]\phi[/tex] = 75.96- 180 = -104.04◦

Thereby in polar form, v can be written like either v= 16.49[tex]\angle255.96[/tex] or, v= 16.49[tex]\angle-104.04[/tex].

From mathematical point of view both the polar forms of v are ok.

My question is that from electrical engineering viewpoint which polar form is to be written i.e. which phase angle is preferred in practice 255.96◦ or -104.04◦?

Let's say we have an AC voltage source in a circuit. In rectangular form it's phasor form is

v= -4 - 16 j .

I want to write this phasor in polar form. Well, The phasor is in 3rd quadrant of complex plane.

It's magnitude comes out to be 16.49

For phase angle,

[tex]\phi[/tex] = arctan (-16/-4) = 75.96◦

To shift 75.96 degrees from 1st quadrant to 3rd quadrant I can approach in 2 ways. like

[tex]\phi[/tex] = 75.96+ 180 = 255.96◦

or,

[tex]\phi[/tex] = 75.96- 180 = -104.04◦

Thereby in polar form, v can be written like either v= 16.49[tex]\angle255.96[/tex] or, v= 16.49[tex]\angle-104.04[/tex].

From mathematical point of view both the polar forms of v are ok.

My question is that from electrical engineering viewpoint which polar form is to be written i.e. which phase angle is preferred in practice 255.96◦ or -104.04◦?