Question

Water is flowing continuously from a tap having an internal diameter $8\times {10}^{-3}m$. The water velocity as it leaves the tap is 0.4 m/s. The diameter of the water stream at a distance $2\times {10}^{-1}m$ below the tap is close to

Answer 1

Diameter $=8\times {10}^{-3}m$
$v=0.4m/s$
$v=\sqrt{u^2+2gh}$
$\sqrt{(0.4{)}^2+2\times 10\times 0.2}$
$=2m/s$
$A_1{v}_1=A_2{v}_2$
$\pi {\left(\frac{8\times {10}^{-3}}{4}\right)}^2\times 0.4=\pi \times \frac{d^2}{4}\times 2d\approx 3.6\times {10}^{-3}m$