Page:A Treatise on Electricity and Magnetism - Volume 1.djvu/295

 The quantity of electricity induced on one of the planes protected by the grating, the other plane being at a given difference of potential, will be the same as if the plates had been at a distance

$\frac{(\alpha-\gamma)\left(b_{1}+b_{2}\right)+\beta_{1}\beta_{2}-4\alpha\gamma}{\alpha+\gamma}$ instead of $b_{1}+b_{2}$.

The values of $$\alpha$$ and $$\gamma$$ are approximately as follows,