plotting – Plot on domain in terms of L from 0 to L

I want to plot a wavefunction with generic length L, without defining L as a particular length. The function is

Subscript((Psi), n)(n_) := (630/L^9)^(1/2) x^2 (L - x)^2

and I want to plot

Plot(Subscript((Psi), n)(1), {x, x0, xf})

where x0=0 and xf=L. I am setting n as a constant, so only x and L are variable. If I define L to be a number, it plots fine, but the plot will look the same no matter what L is, with Subscript((Psi), n)(0)=0, Subscript((Psi), n)(L)=0, maximum at L/2, etc.

I am wondering if there is a way to plot this on a domain in terms of L.