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Old Apr 16th 2011, 06:10 PM   #1
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Quantifying electrical currents through inquiry

Hello again-

It's me Ray again with some more questions about electrical currents. I have attached two problems that I have answers for, but I am not sure if my answers and reasonings are correct.

for 5.3 i know that the total current = i and that

A = 3B

C = 2B

then if I say that B = i/6 this means that

B = i/6
A = 3i/6
C = 2i/6

and since i/6 + 3i/6 + 2i/6 = 6i/6 this must be correct


I am still working on 5.4
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File Type: pdf Scan_Doc0034.pdf (246.4 KB, 3 views)
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Old Apr 16th 2011, 06:27 PM   #2
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Originally Posted by Ray3Ray3 View Post
for 5.3 i know that the total current = i and that

A = 3B

C = 2B

then if I say that B = i/6 this means that

B = i/6
A = 3i/6
C = 2i/6

and since i/6 + 3i/6 + 2i/6 = 6i/6 this must be correct
You are correct, but I think a better presentation would be to say that
i = A + B + C = 3B + B + 2B = 6B

Thus B = i/6, etc.

-Dan
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Old Apr 16th 2011, 06:34 PM   #3
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Thanks Dan-

That does make more sense to present it that way. Is 5.4 really simple and I am making it too hard? Here is what I thought when I first looked:

Since A and C are in series they are both getting .4A through them. So this means that B must have .8A running through it, then the .4A and .8A join up as 1.2A to go through D and back to the battery.
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Old Apr 17th 2011, 07:56 AM   #4
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Originally Posted by Ray3Ray3 View Post
Thanks Dan-

That does make more sense to present it that way. Is 5.4 really simple and I am making it too hard? Here is what I thought when I first looked:

Since A and C are in series they are both getting .4A through them. So this means that B must have .8A running through it, then the .4A and .8A join up as 1.2A to go through D and back to the battery.
Your analysis looks good to me.

-Dan
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