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#### chewy

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Can someone please help me out with the formula for this, I thought it was Total Resistance = R^-1 + R^-1 + R^-1. Ie, 50^-1+100^-1+100^-1 = 0.0201 Obvisouly thats incorrect.

#### chewy

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Sorry forgot the problem.

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#### Barjack

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it's in parallal, R1 x R2 x R3/ R1 + R2 + R3...

Not leaving my VA Boys (ACC) to go look at School Books!

chewy

#### chewy

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Thanks for that.

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#### A Little Short

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Rt= 1/R1 + 1/R2 + 1/R2 +.........

Rt = 1/50 + 1/100 + 1/100

Rt = 0.02 + 0.01 + 0.01

Rt = 0.04

#### Nuzzie

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You know about the reciprocal button on the calculator right (x-1)? Makes these calcs so much quicker. (don't mean to be insulting but a lot of people in my class didn't know this and were using division all the time)

#### chewy

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You know about the reciprocal button on the calculator right (x-1)? Makes these calcs so much quicker
Yep Im using that mate.

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You know about the reciprocal button on the calculator right (x-1)? Makes these calcs so much quicker. (don't mean to be insulting but a lot of people in my class didn't know this and were using division all the time)
You would not believe how many Calculators don't have that button...

Parallel Circuits:

Circuit resistance --- is: (1 / (1/R1 + 1/R2 + 1/R3 + ...)

Voltage --- The voltage drop across all components connected in parallel must equal the supply voltage.

Current --- Total circuit current is equal to the sum of all parallel branch currents

Power --- Total circuit power is equal to the sum of the branch current times the supply voltage. In other words, the I x E power dissipated in each branch of a paralle circuit must add up to be equal to total circuit current time supply voltage.

GO VA

chewy

#### sparky970

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Rt= 1/R1 + 1/R2 + 1/R2 +.........

Rt = 1/50 + 1/100 + 1/100

Rt = 0.02 + 0.01 + 0.01

Rt = 0.04

#### bkmichael65

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it's in parallal, R1 x R2 x R3/ R1 + R2 + R3...

Not leaving my VA Boys (ACC) to go look at School Books!
Product over the sum only works with 2 resistances at a time

#### chewy

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#### A Little Short

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Not according to my "ciphering"!

Too late for this tonight, but I forgot the 1/RT
so.......

1/.04 = 25 ohm

#### chewy

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#### bkmichael65

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I know that... now

I'm trying to figure out what ^ meanx......

There goes my bracket!

#### chewy

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I know that... now

I'm trying to figure out what ^ meanx......
Just means putting what follows it up as an exponent.

#### chewy

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Should be 25 ohms
Seriously? Thats the 3rd typo in this ****ing work book.

#### A Little Short

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You could also make two circuits out of the three since two Rs are the same.
If two R are the same, you can take half of the total of the two.
So (2) 100 R would be 50

Now since the other R is 50 you now have (2) 50 R

So half of 50 = 25

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