stueelad
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I am trying to find the resistor value of Rx in this diagram, can someone please help.
![[ElectriciansForums.net] Resistor value ?](https://electricians.s3.eu-west-1.amazonaws.com/data/attachments/1/1358-91c199bb26e19191a0f2f18308ac0164.jpg "[ElectriciansForums.net] Resistor value ?")
Discuss Resistor value ? in the Electrician Courses : Electrical Quals area at ElectriciansForums.net
here we go, its been a while since i was at college. total resistance= voltage/current (R=V/I) 20/0.25= 80.
Resistance in series = R= r1+r2, so 80-5= 75. so you have 75 ohms to account for. resistance in paralell = 1/r= 1/r1 =1/r2 . so 1/75 -1/10 = 11.53.
Hope i got it right, and that it helps.
Some of the blokes on here are lecturer's so im sure they will be along soon to mark (and fail) me!
Resistance in series = R= r1+r2, so 80-5= 75. so you have 75 ohms to account for. resistance in paralell = 1/r= 1/r1 =1/r2 . so 1/75 -1/10 = 11.53.
Hope i got it right, and that it helps.
Some of the blokes on here are lecturer's so im sure they will be along soon to mark (and fail) me!
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pushrod
im liking bumping into your posts again mate
Cheers
Go on then.
P.S. Empty your PM box
oops done . 3.5A across the 5 ohm resistor (doh! forgotten the code) so 3.25A thru unknown resistor, then 2.5V/3.25A = 0.71 ohms
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J
JUD
Cheers
oops done . 3.5A across the 5 ohm resistor (doh! forgotten the code) so 3.25A thru unknown resistor, then 2.5V/3.25A = 0.71 ohms
I get 0.77Ω.
0.71 is the resistances in parallel [1/r = 1/(1/0.77 + 1/10)]
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pushrod
2.5/3.25 actually equals 0.77 ohms (don't know what's happening to meCheers
oops done . 3.5A across the 5 ohm resistor (doh! forgotten the code) so 3.25A thru unknown resistor, then 2.5V/3.25A = 0.71 ohms
)
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