Uh oh! Wolfram|Alpha doesn't run without JavaScript.
Please enable JavaScript. If you don't know how, you can find instructions
here
.
Once you've done that, refresh this page to start using Wolfram|Alpha.
f(x) = (1/(2*pi*L))*ln(x/D)+ 1/(h*x*pi)-1/U
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random
