Like Problem $7-34$

Statement

A student team is to design a human$-$powered submarine for a design competition. The overall length of the prototype submarine is $4\mathrm{.}85$ m $,$ and its student designers hope that it can travel fully submerged through water at $\backslash (0\mathrm{.}350\backslash$mathrm$\{$~m$\}/\backslash$mathrm$\{$s$\}\backslash ).$ The water is freshwater $($a lake$)$ at $\backslash ($ T$=15\mathrm{.}0^\{\backslash$circ$\}\backslash$mathrm$\{$C$\}\backslash ).$ The design team builds a $\backslash (\backslash$frac$\{1\}\{3\}\backslash )$ scale model to test in their university's wind tunnel $($Fig$.).$ A shield surrounds the drag balance strut so that the aerodynamic drag of the strut itself does not influence the measured drag. The air in the wind tunnel is at $\backslash (25\mathrm{.}0^\{\backslash$circ$\}\backslash$mathrm$\{$C$\}\backslash )$ and at one standard atmosphere pressure. At what air speed do they need to run the wind tunnel in order to achieve similarity? Answer: $\backslash (14\mathrm{.}4\backslash$mathrm$\{$~m$\}/\backslash$mathrm$\{$s$\}\backslash )$