• jesuslovesu
In summary, the conversation discusses the difficulty in determining which phasor leads or lags the other in a phasor diagram. The example given shows a phase difference of 162 degrees, but the answer states a difference of 198 degrees. The main focus is on visually inspecting the diagram to determine the lead/lag relationship.

Homework Statement

Let's say I have
(1) 6<-9
and
(2) 6<189

I don't have a problem drawing the phasors out, however, I am having a bit of difficulty determining how to 'read' the diagram and tell how one leads/lags the other.

In the example I've given, I draw out the phasors but when it comes to determining which one lags the other I am a bit confused.

I can easily find the phase difference (351 - 189 = 162 deg).

Is there a way I can visually inspect each diagram to determine which one leads and which one lags?

Dear jes, -9= 351 its ok but there is 360 degree phase diff (1 full cycle) between them. do u understand my point?

Suppose, in a perfect circular racing path, u start cycling from 0 degree and round a trip 351 degree and then one of ur frnds starts cycling from -9 degree (means ur 351 degree). At that moment u r lead of ur frnd by 351 degree.

However, ur answer of the question is:
Ans: 189 degree leads -9 degree by 198 degree (not 162 degree). (Lets check and discuss with others)
b fine.

Last edited:
Hmm, that's interesting, according to the answer the phase difference should be 162 degrees. I think by convention my book always takes the angle that is less than 180 degrees.

But anyway, I'm really more interested in figuring out how to look at a phasor diagram and see if one phasor leads/lags the other, I just can't quite tell at this point.

1. What is the difference between leading and lagging phasors?

Leading and lagging phasors refer to the phase relationship between two alternating current signals. A leading phasor occurs when one signal reaches its peak value before the other, while a lagging phasor occurs when one signal reaches its peak value after the other.

2. How are leading and lagging phasors represented?

Leading and lagging phasors are represented graphically using vectors. The length of the vector represents the amplitude of the signal, and the angle between the vector and the reference axis represents the phase difference between the two signals.

3. What is the significance of leading and lagging phasors in AC circuits?

Leading and lagging phasors are important in AC circuits because they help us understand the relationship between voltage and current. The phase difference between the two signals affects the power factor of the circuit, which in turn affects the efficiency of the circuit.

4. How do you calculate the phase difference between two signals using phasors?

To calculate the phase difference between two signals using phasors, you first need to convert the signals into their complex number form. Then, you can find the angle between the two complex numbers using the inverse tangent function. This angle represents the phase difference between the two signals.

5. Can phasors be used to analyze non-sinusoidal signals?

Yes, phasors can be used to analyze non-sinusoidal signals as long as the signals are periodic. In this case, the phasors would represent the fundamental frequency component of the signal. However, phasors cannot be used for non-periodic signals.