Specifically I am trying to plot the following:

![Equation][1]

As v_r vs. l, sampling d in digit intervals from d=5 to d=15. Please forgive the specific nature of this question but I am having trouble finding a solution. The domain of l only need be 0 to pi/2.

For the sake of context here is the rest of my visualisation:

Plot[{Evaluate[
   Table[Sin[l]*(2500/Sqrt[100 + d^2 - 20*d*Cos[l]] - 250), {d, 0, 
     5}]], Evaluate[
   Table[Sin[l]*(2500/Sqrt[100 + d^2 - 20*d*Cos[l]] - 250), {d, 15, 
     20}]]}, {l, 0, \[Pi]/2}, AxesLabel -> {l, v}]

![Graph][2]

I have tried using a combination of the Table and Piecewise functions, but to no avail. I would greatly appreciate any help.

Cheers.