Introduction to Phasors

HaroWorld1 points out that the actual phasors component starts at 9:05. The preamble explains why phasors are necessary and the problem they solve.

A quick overview as to how sums of sinusoids with the same frequency can be added use phasors as opposed to using more laborious trigonometry usually required. Also covered is the application of phasors to find voltages across linear circuit elements in series and in parallel with alternating current.

There is one typo where in one slide, I represent 45 degrees as pi/2 and not pi/4. It occurs around 5:45 and thanks to Josh Brown for noting this.

[lordtez]

Finally, someone who can explain WHY Phasors work. Excellent presentation; thank you.

[bassk]

it tools me hours to find a video as thorough as this one. Nicely done, Thanks for being on the camera, standing up strait and speaking clearly. I can't stand people behind the camera in a dark room who mumble no matter who smart they are

[MrExspectator]

Great teaching style, very clear! Thank you, and I hope you upload more lessons!

[robertfaney]

Thank u for this great material, really learnt a lot being 4th year Electrical in USA - fantastic !

[NoseBleedrummer]

Great video, I liked how you gave a strong motivation for actually using phasors.

[ssssssssssurvey]

your lecture is very clear, very good. thanks

[skiptaker]

Amazing comprehensive Lecture...!!
Thanks a lot!

[jakeanderson]

Thank you!  I finally understand this:)

[akinakinyilmaz]

Thank you very much, that is very beneficial for understanding this topic

[AI-robm]

very helpful lecture, thank you very much sir.

[sammao]

Very good lecture, helped me a lot! Thank you! I thought at 29:21 there was an error, purely a calculation one. The total admittance should be: 0.5 - j19.25 = 19.26 ⦟ - 88.51°.
Therefore the total impedance = 0.05192 ⦟ 88.51°.

[douglasdeboer]

Good video.  A correction:  At 21:58 in two instances, the word "conductive" in
  blue text should be replaced by "capacitive" in blue text.

[NauticalAdventure]

Well done. Thank you. However, I do think a little bit more of the lecture should go into adding two phasors and the math that goes into finding the real and imaginary components. Also drawing the triangle of the real and imaginary component to find the Vmax or the hypotenuse of the triangle. Like i said though, well done, it was very clear and easy to understand. I am just inputting advice on where I had to pause the video and dig a little deeper to understand.

[pnichols]

At 14:30 you have a string of complex numbers that you are adding together.  There appears to be a mistake from one line to the next...Shouldn't 12L-90 be 12e^-90i?  Also, When adding the string of complex numbers on Wolfram/Alpha, why doesn't  the website reach the same answer as you?

[andrewzhang]

Very helpful video :) Just another small correction. At around 35:20 you say that the angles are orthogonal and that they differ by 45 degrees. Should be 90 degrees

[glassofwater]

Could you upload the PowerPoint you used during this video?

[HaroWorld]

phasors start at 9:05 if you want to skip the technicals and stuff

[eduardojreis]

Hi, first I want to thank you for this video. Really cool.
Here is my question. At 10:15,  it says that:
-> nu*cos(omega*t + phi) = nu phase phi.
But later, by the Euler's Formulas, it says:
-> nu phase phi = nu*exp(j*phi) = nu(cos(phi) + j*sin(phi)).

But here (14:30), you just go from the trigonometric notation that has only cosine, to the phasor one; then to the complex exponential one, that this one has also a sin in it. 

I got confused: Where did the j*sin(phi) came from, or where did it go in the first case?

[bassk]

13:40 in the video
You do not explain how to go from 12+j9 to 15phasor36.87
Nor does my book. That is the answer i have been searching for since 8am this morning. So frustrating that everyone skips that step. You can not use an inverse trig function because it is UNDEF

[bassionbean]

Wait.... Don't you also need to multiply the root mean square value (root 2) to the amplitude v if you're converting to a sinusoid? 15:47 is wrong I'm pretty sure... University of Nottingham's interactive gave me this piece of info.