Equivalent Resistance of a Ciruit

AI Thread Summary
The discussion focuses on calculating the equivalent resistance of a circuit with specific resistor values. Participants suggest methods for combining resistors in series and parallel, with some initial confusion about the arrangement. The correct approach involves combining R3 and R4 in series, then placing R5 in parallel with that combination, followed by adding R2 in series. Additionally, R6 and R7 should be combined in series and then placed in parallel with R1. Ultimately, the final equivalent resistance can be calculated using the parallel resistor formula for the resulting combinations.
Kajayacht
Messages
27
Reaction score
0
1. Find the equivalent resistance of the circuit as shown in the diagram below; where R1 = 1 Ω, R2 = 2 Ω, R3 = 2 Ω, R4 = 4 Ω, R5 = 1 Ω, R6 = 1 Ω, and R7 = 2 Ω.
[URL]http://img21.imageshack.us/i/prob06v2.gif/[/URL]

http://img21.imageshack.us/i/prob06v2.gif/

Homework Equations



R(parallel) 1/R(total) = 1/R1 + 1/R2
R(series) R(total) = R1 + R2

The Attempt at a Solution



I know I can do this one, its easy. But the arrangement of the resistors is throwing me off

I think I can take R3 and R4 in series, then take R5 in parallel with R3,4, take that in series with R2.

Then R7 and R6 are in series, and R7,6 is in parallel with R1. R1,7,6 in series with R2,5,3,4

Is this right?
 
Last edited by a moderator:
Physics news on Phys.org
not 100% on this but here's my help. id do r3,4 in a series, then Rt of that with r5 in a parallel. then the rt3,4,5 with R2 in a series. r7 and r6 are a series so just add those. then i believe you can just do the 3 final resistances all in one parallel circuit.
 
Kajayacht said:
I know I can do this one, its easy. But the arrangement of the resistors is throwing me off

I think I can take R3 and R4 in series, then take R5 in parallel with R3,4, take that in series with R2.

Then R7 and R6 are in series, and R7,6 is in parallel with R1.

This is correct.

Kajayacht said:
R1,7,6 in series with R2,5,3,4

Is this right?

This is not correct.
 
After you have added together R7 and R6, you should have 3 resistors in parallel:
1. R1
2. R6 + R7
3. The resistor you got from merging R2, R3, R4 and R5

Use the parallel resistor formula on all three to get R Total

Kajayacht said:
...the arrangement of the resistors is throwing me off

When I used to have this problem, I found that redrawing the circuit makes it easier to see which resistors are in parallel :)
 
is what i wrote correct?
 
Thanks guys, I got it now. R1,7,6 should be in parallel with R2,5,3,4 not series.
 
Thread 'Voltmeter readings for this circuit with switches'
TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
Thread 'Struggling to make relation between elastic force and height'
Hello guys this is what I tried so far. I used the UTS to calculate the force it needs when the rope tears. My idea was to make a relationship/ function that would give me the force depending on height. Yeah i couldnt find a way to solve it. I also thought about how I could use hooks law (how it was given to me in my script) with the thought of instead of having two part of a rope id have one singular rope from the middle to the top where I could find the difference in height. But the...

Similar threads

Replies
5
Views
1K
Replies
11
Views
2K
Replies
3
Views
5K
Replies
9
Views
3K
Replies
3
Views
2K
Replies
9
Views
1K
Replies
2
Views
1K
Back
Top