You can put this solution on YOUR website! Make V the subject:
R=(2r)/(2-V^2r)
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Note: I cannot tell if the exponent on V is 2 or 2r
I'll assume it is 2
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Invert both sides to get:
(2-V^2*r)/(2r) = 1/R
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Multiply both sides by 2r to get:
2-V^2*r = 2r/R
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Subtract 2 from both sides to get:
-V^2*r = [2r/R] - 2
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Divide both sides by -r to get:
V^2 = [(2/r - 2/R]
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Simplify the right side to get:
V^2 = [(2R-2r)/(r*R)]
Take the sqrt of both sides to get:
V = sqrt[2(R-r)/(r*R)]
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Cheers,
Stan H.
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