At a sudden contraction in a pipe the diameter changes From D1 to D2. The pressure drop,...

At a sudden contraction in a pipe the diameter changes From D₁ to D₂. The pressure drop, , which develops across the contraction, is a function of D₁ and D₂, as well as the velocity, V, in the larger pipe, and the fluid density, p, and viscosity, μ, Use D₁, V, and μ as repeating variables to determine a suitable set of dimensionless parameters. Why would it be incorrect to include the velocity in the smaller pipe as an additional variable?