Consider the equation `T = 2pi sqrt(l/g)` and check whether it is correct or not.

Explanation

We know, dimensional formulae of `T, l and g ` are `[T], [L], [LT^(-2)]` respectively.
`:.` Dimensional formula of `sqrt(l/g) = sqrt(L/(LT^(-2))) = sqrt(T^2) = [T]`
Dimensional formula of left side is also [T]. As `2 pi` is a dimensionless quantity, the dimensional formula of left hand side of hte equation is equal to dimensional formula of right hand side. Hence we conclude that the given equation is correct one.