lets keep it simple,
Assume 1/2.roh.s to be constant and lets give it a value of 1
now V sq is the only variable
Next lets try some values
15 sq=225
increase 15 to say 20 and we have
20sq=400
similarly
150 sq=22500
200sq=40000
so a small increase to v gives us a large increase to the figure on the right.
Hope that explains the puzzle.