parallel resistance.

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searley

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A resistor network with three resistors 9Ω, 3Ω, 12Ω are connected in parallel. What will their combined resistance be:

can i work this out on a scientific calculator ? cheers.

 

searley

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i try`ed 1 over 9 + 1over 3 + 1 over 12 and i got 0.52.the answer on the sheet is 1.89 ohms :_| :_| :_| .

 
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i try`ed 1 over 9 + 1over 3 + 1 over 12 and i got 0.52.the answer on the sheet is 1.89 ohms :_| :_| :_| .
As Theory said..

1/Rt=1/r +1/r +1/r
but you may just need to check the number of decimal places you are working to

e.g.

1/9 = 0.111

1/3 = 0.333

1/12 = 0.083

= 0.527

1/0.527 = 1.89

WHEREAS 1/0.52 = 1.92!!!

Not sure what the trend is nowadays..

But I was told as a general rule.. (unless specified in the question)..

work to 3 decimal places for added bit of accuracy without having reams of long numbers written down. ;)

 

Mr Sworld

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A resistor network with three resistors 9Ω, 3Ω, 12Ω are connected in parallel. What will their combined resistance be:can i work this out on a scientific calculator ? cheers.
How did you get the Ohm symbol to appear?

 

Theorysparky

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How did you get the Ohm symbol to appear?
ΩΩΩ

the only way i got it was to open a word document,,,,,,symbols

copy + paste and i bet thats the long way round:O

 
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ΩΩΩthe only way i got it was to open a word document,,,,,,symbols

copy + paste and i bet thats the long way round:O
you could just copy it from the post on this ere fornum:p:p:pGuiness Drink

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makes me feel like burstin into song...

Guiness DrinkGuiness Drink

ohm ohm on the range...

where the deer and the antelope play...

there seldom is heard...

a discouraging word.........

BlushingBlushing

oops

sorry!!! :(

I am now sitting back in me corner...

and I am about to put m y h a n d s o n m e h e a d.

{had to type them last bits with me nose... and this bit was typed..

and copied earlier.. then just pasted with me nose! :p :|}

 
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