$D=0,12\,\,\left( m \right)\,\,\to \,\,R=0,06\,\,\left( m \right)$
$l=0,08\,\,\left( m \right)$
$L=50\,\,\left( m \right)$
………………………
Số vòng dây:
$N=\dfrac{L}{C}=\dfrac{L}{2\pi R}=\dfrac{50}{2\pi .0,06}=\dfrac{1250}{3\pi }$ ( vòng )
Hệ số tự cảm:
$L=4\pi {{.10}^{-7}}\dfrac{{{N}^{2}}}{l}S$
$L=4\pi {{.10}^{-7}}\dfrac{{{N}^{2}}}{l}\pi {{R}^{2}}$
$L=4\pi {{.10}^{-7}}\dfrac{{{\left( \dfrac{1250}{3\pi } \right)}^{2}}}{0,08}\pi .0,{{06}^{2}}$
$L=3,{{125.10}^{-4}}\,\,\left( H \right)=0,3125\,\,\left( mH \right)$