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Re: Resistance

PostPosted: March 3rd, 2017, 7:04 am
by rajnz00
Sorry Dave you have made a mistake. I sat down and worked it out. I used a different method and got 1.130

You have made a mistake in your second diagram. This is how it should be:

Sorry not being able to paste my picture but the second 2 ohms should be connected at the end and not the middle. When you do that, you get the same answer as me.

Re: Resistance

PostPosted: March 3rd, 2017, 2:04 pm
by vivian maxine
neuro » April 26th, 2014, 2:31 pm wrote:Got it, Canadys.

I do have a deformed perspective, but in my defense I beg you to consider the fact that all "channels" in the human body (which is my field) are closed pipes.... :°)


Forgive me for my tardiness in coming to this but I can't resist. I must ask: "Like the wind tunnel from our lungs to our nasal passages?

Re: Resistance

PostPosted: March 3rd, 2017, 2:08 pm
by rajnz00
OK Here is it - the correct configuration:

Image

Re: Resistance

PostPosted: March 4th, 2017, 6:16 am
by Dave_Oblad
Hi Raj,

I don't see your alternate configuration above. I just see the word "Image".

To have a constant Image, it must be uploaded to this site using the "Upload Attachment" option in the full Editor and then Placed In-Line within your posting.

Could you try again?

Note: Threads get <Locked> when they stray too far from the OP (as we (and others) did) in the "Time" thread.

Best Regards,
Dave :^)

Re: Resistance

PostPosted: March 4th, 2017, 6:39 am
by rajnz00
How come you cant see the image when I can?
Anyway here it is again
RT.jpg

Re: Resistance

PostPosted: March 4th, 2017, 6:46 am
by rajnz00
PS I was going along quite nicely till you asked them to shut me down. Thanks for that. In science you have such posts as "Backward Land" and "What the heck is Time" which haven't been shut down. Whereas mine "What causes the direction of time" was shut down pretty quick. Wonder why the special treatment.

Re: Resistance

PostPosted: March 4th, 2017, 7:23 am
by Dave_Oblad
Hi Raj,

Not Special Treatment.. We just strayed too far from the OP (talking about global diameters and resistance etc).

Here is my breakdown again:

Solution.jpg
My Solution Breakdown in steps

Note: The first stage conversion in my Upper Right is not the same as yours as indicated in Red.

Mistake.jpg
Your incorrect Breakdown for step 1

This makes the center (2-ohm) pair a 1 Ohm (as shown) with a single 2 ohm on the far right. I circled the incorrect placement in your breakdown.

Can you see your error?

BTW, I hate this problem. My mean spirited Professor thought abusive usage of his Power/Authority would just force me to another school. But.. since I lost my draft deferment.. it also put my life in jeopardy in the Vietnam War (luckily I survived). This was around 1970 and he was already about +60. So I'm sure he is dead by now.

I hate Bullies and they come in all flavors (Physical and Authority).

Regards,
Dave :^)

Re: Resistance

PostPosted: March 4th, 2017, 3:11 pm
by rajnz00
Dave, I'm afraid you are wrong. It's not me who has made the error but you. Surely you can see it.
RT2.jpg


Cant you see that you have joined up C with A and and D with B when they come after them. OIC it is the last one which is in the middle.

So yep you are right. But for the wrong reasons. I have correctly placed A and B but incorrectly the extreme right side resistance. But now I am not sure whether that would be so, because when I calculated RT going from each loop in the the right hand side onwards I still got 26/23

Re: Resistance

PostPosted: March 4th, 2017, 3:25 pm
by rajnz00
Here is what I did before looking at your diagram:
RT3.jpg

RT4.jpg

Re: Resistance

PostPosted: March 4th, 2017, 4:00 pm
by rajnz00
I made a mistake in step 2
1/RT = 2/3+1/6 = 5/6
RT = 6/5
So in the final step
1/RT = 1/2 + 1/(3 1/5) = 1/2 + 5/16 = 13/16
RT = 16/13 = 1.231

Anyway I'm outa here

Re: Resistance

PostPosted: March 4th, 2017, 4:16 pm
by Dave_Oblad
Hi Raj,

Given:

Bridge.jpg
Simple Bridge

If we replace RT with a Battery, then the voltage will distribute itself around the circuit.
Given that distribution, we will see no voltage differential at points A & B above.
Thus RX has no effect.. you can remove it... or replace it with a short.
RX has no effect on RT as shown above.

Now look again at the same technique applied below:

Correct.jpg
The same Technique for SB1 and SB2

If we replace RT with a Battery, it should be obvious that there will be no differential between the Green Dots for the Bridge made of 1 ohm resistors and no differential between the Blue Dots for the Bridge made of 3 ohm resistors. Thus the Green Dots can be shorted with SB1 and the Blue Dots can be shorted with SB2. These shorts (SB1 & SB2) have no effect on RT. This places RB and RD in parallel as shown in the next diagram.

That is why your redraw is incorrect as you previously have shown.

Now solve for the Right Side Circuit and you will get the correct answer.

Best Wishes,
Dave :^)

Re: Resistance

PostPosted: March 4th, 2017, 4:28 pm
by rajnz00
Yes you are right. I pointed this out earlier "I have correctly placed A and B but incorrectly the extreme right side resistance." which you have named D
I possibly made a mistake in my calculations but cant be bothered now.