Find the dimensional formula of `(1)/(4 pi "in"_0) (e^2)/(hc)`, where symbols have their usual menaing.

Answer

`[M^0L^0T^0]`

Explanation

`(e^2)/(4pi "in"_0hc) = (F r^2)/(hc), where F =(e^2)/(4pi "in"_0r^2)`
`=([MLT^(-2)][L^2])/([ML^2T^(-1)][LT^(-1)]) =1 = [M^0 L^0T^0]`