# Anybody know anything about series circuits?



## HusqyPro (Aug 3, 2009)

Getting caught up on class work.

Can somebody explain this relationship/formula in plain English? I thought it would come back to me since I was an EM3 in the USCG but nada.

Rt= 20ohms It= 5A Et= 100V Pt=500W
R1= 5ohms I1= 5A E1= 25V P1=125W
R2= 10ohms I2= 5A E2= 50V P2= 230W
R3= 5ohms I3= 5A E3= 25V P3= 125W

Any advice appreciated!:thumbsup:


----------



## naptown CR (Feb 20, 2009)

Unless you are doing really old Christmas tree lights this is useless information. Pretty much everything is done in paralell now.


----------



## HusqyPro (Aug 3, 2009)

Useless or not I gotta know it if I want to pass the class.

Got an exam on Thursday, throw me a bone brother!


----------



## Leo G (May 12, 2005)

Rt= 20ohms It= 5A Et= 100V Pt=500W
R1= 5ohms I1= 5A E1= 25V P1=125W
R2= 10ohms I2= 5A E2= 50V P2= 230W
R3= 5ohms I3= 5A E3= 25V P3= 125W

Resistant total = 20 ohms, Current total = 5 amps, Voltage total = 100v, Power total = 500w

R1+R2+R3=Rt
In a series circuit the current is constant
25v+50v+25v= 100v (Et)
125W+250W+125W=500W (there is an error in your statement, 5Ax50v=250W)

I x E = P
E / I = R

You can move these equations around to suit your need and figure out the missing data

P/E=I
P/I=E

R/E=I
R/I=E

Any more questions?:whistling


----------



## HusqyPro (Aug 3, 2009)

Holy hell. Ummm, this is harder than I thought.

Here's the one I'm trying to solve now:

Rt= ?ohms It= ?A ET= ?V Pt= 625W
R1= ?ohms I1=?A E1= ?V P1= ?W
R2= 100 ohms I2= 2A E2= ?V P2= ?W
R3= ?ohms I3= ?A E3=50V P3= ?W

I don't think I have enough data to solve that problem? Do I? I think I need more of the ? filled in so I can solve it.


----------



## Leo G (May 12, 2005)

So, are you asking me to give you the answer? It's gonna cost you your desert ya know. And no frik'n fruit.:laughing:


----------



## Kgmz (Feb 9, 2007)

HusqyPro said:


> Getting caught up on class work.
> 
> Can somebody explain this relationship/formula in plain English? I thought it would come back to me since I was an EM3 in the USCG but nada.
> 
> ...


 
That is just basic Ohm's Law.


From first line in example
Amps x Volts = Watts 5A x 100V = 500W
Watts / Volts = Amps 500W / 100V = 5A
Watts / Amps = Volts 500W / 5A = 100V

Volts / Amps = Ohms 100V / 5A = 20ohms
Amps x Ohms = Volts 20 ohms x 5A = 100V


The third line is wrong, should be 250 watts.



Just do a web search, there are some good sites about Ohm's Law in Series and Parallel Resistive circuits


----------



## Kgmz (Feb 9, 2007)

Leo beat me to it.


----------



## naptown CR (Feb 20, 2009)

Leo G said:


> Rt= 20ohms It= 5A Et= 100V Pt=500W
> R1= 5ohms I1= 5A E1= 25V P1=125W
> R2= 10ohms I2= 5A E2= 50V P2= 230W
> R3= 5ohms I3= 5A E3= 25V P3= 125W
> ...


Check out the head on Leo:clap::clap::clap:


----------



## HusqyPro (Aug 3, 2009)

Leo is freaking smart.

No, not asking for the answer. Just trying to get caught up on what the class is doing. Missed the first two weeks because I was having heart surgery. 

I don't want to be too far behind, especially since I'll be missing more class time with radi, chemo, and more surgery.

So to fnd the t line I work back from 625 watts? TheI line is going to be 2A all the way because amperage doesn't change in a series circuit?


----------



## Leo G (May 12, 2005)

Rt= ?ohms It= ?A ET= ?V Pt= 625W
R1= ?ohms I1=?A E1= ?V P1= ?W
R2= 100 ohms I2= 2A E2= ?V P2= ?W
R3= ?ohms I3= ?A E3=50V P3= ?W


Ok, I'll see if I can walk you through it. 

Current is constant through the system so all of the I=2A

You have 625W for the Pt and you have a current so you should be able to figure out Et

P3 is also figured out for you because you know that I=2A

Because now you know I3 and E3 you can figure out R3

Because you know R2 and I2 you can figure out E2 and then P2

Now the rest is figured out from subtraction Because you know equation 2 and 3 you just have to put in what must remain to get the total equation.


----------



## naptown CR (Feb 20, 2009)

HusqyPro said:


> Leo is freaking smart.
> 
> No, not asking for the answer. Just trying to get caught up on what the class is doing. Missed the first two weeks because I was having heart surgery.
> 
> ...


Yo Bob maybe your health comes first?


----------



## HusqyPro (Aug 3, 2009)

So far I have:

Rt= 156.25ohms It=2A Et=312.5V Pt= 625W

Close?


----------



## HusqyPro (Aug 3, 2009)

naptown CR said:


> Yo Bob maybe your health comes first?


Actually I feel much better. I can walk to the truck without gasping for breath, feeling faint, and with a racing pulse.

Amazing what a new pacemaker can do.:thumbsup:


----------



## Static Design (Nov 30, 2008)

Thanks leo for typing that out, I was fixing to do it for him: Now I can go back to this rendering.


----------



## Leo G (May 12, 2005)

HusqyPro said:


> So far I have:
> 
> Rt= 156.25ohms It=2A Et=312.5V Pt= 625W
> 
> Close?


:notworthy Very good grasshopper

Now let us introduce you to variable frequency in a capacitance/impedance circuit in a 3 phase system......:shutup:


----------



## Leo G (May 12, 2005)

Full Spool said:


> Thanks leo for typing that out, I was fixing to do it for him: Now I can go back to this rendering.


Electronic cabinet maker to the rescue.....arty:


----------



## HusqyPro (Aug 3, 2009)

Final answer:

Rt= 156.25ohms It= 2A Et=312.5V Pt=625W
R1= 1.25ohms I1= 2A E1= 62.5V P1= 125W
R2= 100ohms I2=2A E2= 200V P2= 400W
R3= 25ohms I3=2A E3= 50V P= 100W

I don't know how it works, but it looks rigt to me.

This is why electricians make $100+ an hour.


----------



## Leo G (May 12, 2005)

You got the numbers right but R1 is written wrong.


----------



## Leo G (May 12, 2005)

So when you get to parallel circuits just remember that the voltage is constant and the current is variable.


----------

