# Desperate NEED OF HELP series-parallel circuits

Discussion in 'General Electronics Chat' started by iceman_blazin, Oct 22, 2007.

1. ### iceman_blazin Thread Starter New Member

Oct 21, 2007
6
0
o-------------------------------o
-......................-.....................-
-......................-.....................-
-...............R1 200ohm.........R3 150 ohm
-.....................-......................-
60v...................-....................-
-.......................-....................-
- ....................... - ................. -
- .........................-........................-
-................R2 100 ohm .........R4 350 ohm
- ......................-.......................-
- .......................- .........................-
-........................-........................ -
o-------------------------------------o
Hey, i am trying to find the (EIR) like the chart version and i have no clue on how to solve this problem i missed the day he went over it and now i am stuck and just need help so if you can show me how to solve this that would be great thank you in advance
- = flow of current
. = so the picture will come out fine

2. ### Dave Retired Moderator

Nov 17, 2003
6,960
146
It might help if you could scan in and upload your circuit because I like many probably cannot decipher your OP drawing.

Is it supposed to be a 60V source with R1 in series with R3, R2 in series with R4, and both these two series arrangements in parallel with each other?

Dave

3. ### Management Active Member

Sep 18, 2007
306
0
I think that since '-' is the flow of current that the battery is in parallel with both the series connections R1 - R2 and R3 - R4. This might have went over my head but what is EIR? I know Equivalent Resistance but what is I ... current?

4. ### iceman_blazin Thread Starter New Member

Oct 21, 2007
6
0
sorry about that here is a attachment

File size:
24 KB
Views:
19
5. ### iceman_blazin Thread Starter New Member

Oct 21, 2007
6
0
E- volts
I - current
R - Resistance

6. ### Management Active Member

Sep 18, 2007
306
0
Well do you know Ohms Law of E = IR? Resistors in series and circuit elements in parallel. That battery is in parallel with both sections of resistors. Also, when the the same current runs through two or more resistors they are said to be in series. What can you so with resistors in series? And since the bettery is in parallel, you should be able to figure out the math calculations with Ohm's Law.

7. ### Dave Retired Moderator

Nov 17, 2003
6,960
146
I don't have Word installed on this PC so can't look at your specific query. Can I point you in the direction of the reference section in the e-book that will be of use:

Deal with the series elements first, then the parallel elements. Also remember:

For components in series, the current through them is the same.

For components in parallel, the voltage across them is the same.

Dave

8. ### iceman_blazin Thread Starter New Member

Oct 21, 2007
6
0
yeah i was told to combine the resistors, and i dont know how to do that, like R1+R2 and R3+R4, then to solve for the resistance and then go back with teh resistance and solve for the voltage but i kinda need step by step or i really wouldnt kno whow to do it what program do you have i can do another link

Oct 21, 2007
6
0

File size:
700 bytes
Views:
13

Apr 26, 2005
3,403
1,230
11. ### iceman_blazin Thread Starter New Member

Oct 21, 2007
6
0
i seen that but one more question, it really doesnt show where or how i combine resistors when they are in a series, do i just add the Ohms together to get a grand total and then when i find the current then plug in to find the volts?

12. ### Management Active Member

Sep 18, 2007
306
0
Yes you are right in your assumption. When resistors are in series (same current) that can be combined by add their resistances together. Keep in mind you are also adding the individual voltages of each together as well to combine to get the total voltage across them both.

V = IR1 + IR2 = I*(R1+R2)

But like Dave said, components in parallel have the same voltage. This includes sources as well like your 60V battery.