Missing Something

[basejumper31]

Hi,

Firstly, sorry if this is the wrong forum, it's kind of a learning question, because I'm doing some online learning of my own before embarking on the lvl 2 2365, and so I'm not yet a trainee and as such can't post in the training forums. I will ofc move this thread if asked to / told where to put it.

Anyway. My issue is this. I've recently been doing some learning / note taking on RLC circuits, and this evening in specific decided to have a closer look at Power Factor.

I got to 2:12 into this video

https://www.youtube.com/watch?v=iQcrmqKeL4Y

And so far have been following it all fine, but here, he's working out the Impedance of the circuit using the equation

[FONT=Times New Roman, serif]Z= R x XL / [FONT=Times New Roman, serif]√[/FONT] (R[SUP]2 [/SUP]xXL[SUP]2[/SUP])
which for the circuit in question (see video) can be written as:
[/FONT]
[FONT=Times New Roman, serif]Z= 2200 x 2827.433 / [FONT=Times New Roman, serif]√[/FONT](2200[SUP]2 [/SUP]x 2827.433[SUP]2[/SUP])
which I get, but then the next stage of the working out, he loses me, because according to him, the above then equates to
[/FONT]
[FONT=Times New Roman, serif]Z= 6220352.6 / 3582.15
Where is he getting 3582.15 from?! When I work out the previous stage of his working, i.e.
[/FONT]Z = 2200 x 2827.433 / [FONT=Times New Roman, serif]√[/FONT] (2200[SUP]2 [/SUP]x 2827.433[SUP]2[/SUP])
I get Z = 6220352.6 / 6220352.6, which obviously = 1


Probably going to look like an idiot, know I've missed something obvious. Still it is late, and it's been a long day, plz don't judge me lol

Thanks for reading

 

[Sintra]

Hi,

Firstly, sorry if this is the wrong forum, it's kind of a learning question, because I'm doing some online learning of my own before embarking on the lvl 2 2365, and so I'm not yet a trainee and as such can't post in the training forums. I will ofc move this thread if asked to / told where to put it.

Anyway. My issue is this. I've recently been doing some learning / note taking on RLC circuits, and this evening in specific decided to have a closer look at Power Factor.

I got to 2:12 into this video

https://www.youtube.com/watch?v=iQcrmqKeL4Y

And so far have been following it all fine, but here, he's working out the Impedance of the circuit using the equation

Z= R x XL / √ (R[SUP]2 [/SUP]xXL[SUP]2[/SUP])
which for the circuit in question (see video) can be written as:

Z= 2200 x 2827.433 / √(2200[SUP]2 [/SUP]x 2827.433[SUP]2[/SUP])
which I get, but then the next stage of the working out, he loses me, because according to him, the above then equates to

Z= 6220352.6 / 3582.15
Where is he getting 3582.15 from?! When I work out the previous stage of his working, i.e.
Z = 2200 x 2827.433 / √ (2200[SUP]2 [/SUP]x 2827.433[SUP]2[/SUP])
I get Z = 6220352.6 / 6220352.6, which obviously = 1


Probably going to look like an idiot, know I've missed something obvious. Still it is late, and it's been a long day, plz don't judge me lol

Thanks for reading

The formula should be Z= R x XL / √ (R2 + XL2) try the calculation now.

 

[Richard Burns]

Change the 2200² x 2827.433² to 2200² + 2827.433²
this gives 3582.15

 

[basejumper31]

Thanks guys

 

[basejumper31]

Another question about the same video (https://www.youtube.com/watch?v=iQcrmqKeL4Y)

At 3:13 there are three lines of calculus on the screen. On the second line it says Irms = 120 and then there is a special character.

I am not familiar with this mathematical operator. Can someone please tell me what it's called so I can look it up.

I could have a bash at deducting what it is from the results he gets from it, but it's too late/early and I'm tired.

Thanks in anticipation

 

[Richard Burns]

it is just an angle symbol, showing a number then the phase angle