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    Just wondering how you would rearrange the restistance equation 1/R=1/R1+1/R2. I thought I did it correctly but every website does something different so just wanted to check. Thankyou
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    well I like R=1/((1/R1)+(1/R2)...)

    cos it keys nice and easily on my very oldschool calculator without textbook entry.

    e.g. for 470 ohm in parallel with 620 ohm

    [4][7][0] [1/x] [+] [6][2][0] [1/x] [=] [1/x]

    267.3
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    (Original post by Joinedup)
    well I like R=1/((1/R1)+(1/R2)...)

    cos it keys nice and easily on my very oldschool calculator without textbook entry.

    e.g. for 470 ohm in parallel with 620 ohm

    [4][7][0] [1/x] [+] [6][2][0] [1/x] [=] [1/x]

    267.3
    Thankyou. That's what I got too but didn't know if I had to simplify it
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    To simplify it, make the denominator the same by multiplying them:
    1/R = [ R2 / (R1R2) ] + [ R1 / (R1R2) ]
    = (R2 + R1) / R1R2
    Then, flip both sides of the equation:
    R = R1R2 / (R1+R2)

    Hope this help
 
 
 
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