T Thread Starter trav Joined Dec 8, 2011 7 Dec 13, 2011 #1 Does anybody know the formula to calculate for a unknown inductor?
T Thread Starter trav Joined Dec 8, 2011 7 Dec 13, 2011 #3 Well I've got the formula F = 1 / 2pi sqrt L x C and need rearrange to find L but dont really know if my answer is correct.
Well I've got the formula F = 1 / 2pi sqrt L x C and need rearrange to find L but dont really know if my answer is correct.
T Thread Starter trav Joined Dec 8, 2011 7 Dec 13, 2011 #4 I got the formula of L = 1 / 4(pi^2)(f^2)xC anyone can clarify this?
thatoneguy Joined Feb 19, 2009 6,359 Dec 14, 2011 #5 Is this for a simple, air core inductor with a single winding? Or to determine the Fo of an LC circuit? I see both your formulas have f and C in your equations. I must admit I do not understand the question you are asking. There is a formula for a wound air coil of Length L and diameter d with a winding density factor. There is a formula for an inductor wound on a ferrite core, but the permiability of the core would be needed. The resonant frequency, \(F_o=\frac{1}{2 \pi sqrt{L C}}\) Please be more verbose with your question, explaining what you do know, and what you'd like to figure out. First, keep in mind: \(\omega=2\pi F\) and \(F=\frac{\omega}{2\pi}\) --ETA: Your Post #3 states you want to solve \(F_o=\frac{1}{2 \pi sqrt{L C}\) The equation is derived from: \(\omega=sqrt{\frac{1}{LC}\) to get L out, we need to square both sides: \(\omega^2=\frac{1}{LC}\) now we can "swap" the left with the denominator \(LC=\frac{1}{\omega^2}\) woops, moved one too many: \(L=\frac{1}{\omega^2 C}\) Obviously, the formula is the same to find C if you know f and L \(C=\frac{1}{\omega^2 L}\) Last edited: Dec 14, 2011
Is this for a simple, air core inductor with a single winding? Or to determine the Fo of an LC circuit? I see both your formulas have f and C in your equations. I must admit I do not understand the question you are asking. There is a formula for a wound air coil of Length L and diameter d with a winding density factor. There is a formula for an inductor wound on a ferrite core, but the permiability of the core would be needed. The resonant frequency, \(F_o=\frac{1}{2 \pi sqrt{L C}}\) Please be more verbose with your question, explaining what you do know, and what you'd like to figure out. First, keep in mind: \(\omega=2\pi F\) and \(F=\frac{\omega}{2\pi}\) --ETA: Your Post #3 states you want to solve \(F_o=\frac{1}{2 \pi sqrt{L C}\) The equation is derived from: \(\omega=sqrt{\frac{1}{LC}\) to get L out, we need to square both sides: \(\omega^2=\frac{1}{LC}\) now we can "swap" the left with the denominator \(LC=\frac{1}{\omega^2}\) woops, moved one too many: \(L=\frac{1}{\omega^2 C}\) Obviously, the formula is the same to find C if you know f and L \(C=\frac{1}{\omega^2 L}\)
debjit625 Joined Apr 17, 2010 790 Dec 14, 2011 #6 @trav I also didn't understood your question... Anyway to find out inductance for a coil you can use Wheeler's Formula \( Inductance (\mu H) = {{0.8(NA)^2} \over {6A + 9B + 10C}} \) where N = number of turns A = average coil radius B = coil length C = coil thickness Note All quantities are in inches and the result is in microhenries \((\mu H)\). Good Luck
@trav I also didn't understood your question... Anyway to find out inductance for a coil you can use Wheeler's Formula \( Inductance (\mu H) = {{0.8(NA)^2} \over {6A + 9B + 10C}} \) where N = number of turns A = average coil radius B = coil length C = coil thickness Note All quantities are in inches and the result is in microhenries \((\mu H)\). Good Luck
Adjuster Joined Dec 26, 2010 2,148 Dec 14, 2011 #7 The OP's problem appears to be stated in terms of the resonant frequency in a tuned circuit, not the coil's construction.
The OP's problem appears to be stated in terms of the resonant frequency in a tuned circuit, not the coil's construction.