Answer
The flow speed in the input tube is 2.8 cm/s
Work Step by Step
We can use the tank dimensions to find the volume flow rate.
$flow~rate = \frac{V}{t}$
$flow~rate = \frac{(0.36~m)(1.0~m)(0.60~m)}{(3.0~hr)(3600~s/hr)}$
$flow~rate = 2.0\times 10^{-5}~m^3/s$
The volume flow rate in the input tube is the flow speed times the cross-sectional area of the input tube.
$flow~rate = v~A = 2.0\times 10^{-5}~m^3/s$
$v~\pi ~r^2 = 2.0\times 10^{-5}~m^3/s$
$v = \frac{2.0\times 10^{-5}~m^3/s}{\pi~r^2}$
$v = \frac{2.0\times 10^{-5}~m^3/s}{(\pi)(0.015~m)^2}$
$v = 0.028~m/s = 2.8~cm/s$
The flow speed in the input tube is 2.8 cm/s.