A liquid of density $\rho $ is coming out of a hose pipe of radius $a$ with horizontal speed $v$ and hits a mesh. $50\%$ of the liquid passes through the mesh unaffected. $25\%$ looses all of its momentum and $25\%$ comes back with the same speed. The resultant pressure on the mesh will be
A$\frac{1}{4}\,\rho {v^2}$
B$\frac{3}{4}\,\rho {v^2}$
C$\frac{1}{2}\,\rho {v^2}$
D$\rho {v^2}$
JEE MAIN 2019, Diffcult
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B$\frac{3}{4}\,\rho {v^2}$
b $F = \frac{1}{4} \times \rho A{v^2} + \frac{1}{4}2\rho a{v^2}$
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