Water flows along horizontal pipe whose cross-section is not constant. The pressure is 1 cam of Hg, where the velocity is 35 cm/s . At a point where the velocity is 65cm/s then pressure will be

Options

A. 0.89 cm of Hg
B. 8.9 cm of Hg
C. 0.5 cm of Hg
D. 1 cm of Hg

Answer

A

Explanation

In horizontal pipe,
`p_(1)+(1)/(2)rhov_(1)^(2)=p_(2)+(1)/(2)rho v_(2)^(2)`
Here, `p_(1)=rho_(m)gh_(1)=13600xx9.8xxh implies rho=1000 kgm^(-3)`
`v_(1)=35xx10^(-2) ms^(-1) implies v_(2)=65xx10^(-2) ms^(-1)`
`therefore` From Eq. (i), we get
`13600xx9.8xx10^(-2)=(1)/(2)xx1000 xx(0.35)^(2)`
`=13600xx9.8xxh+(1)/(2)xx1000xx(0.65)^(2)`
After solving, 0.89 cm of Hg.