Physics - Fluid Question with Solution | TestHub

Area of the cross-section of the tube,$a={10}^{-2} {\mathrm{m}}^{-2}$

Speed of stream of water$=15 \mathrm{m} {\mathrm{s}}^{-1}$

$V=$The volume of water coming out per second from the tube$=a\times v=15\times {10}^{-2} {\mathrm{m}}^3 {\mathrm{s}}^{-1}$

$$Also, we know that the density of water striking the wall per second, then

$m=pV={10}^3\times 15\times {10}^{-2}\mathrm{ }\mathrm{kg} {\mathrm{s}}^{-1}=150\mathrm{ }\mathrm{kg} {\mathrm{s}}^{-1}$

As on hitting the wall, water does not rebound, so

$F=$change in momentum per second

$=$mass of water flowing out per second$\times$velocity

$= 150\times 15=2250\mathrm{ }\mathrm{N}$