A horizontal pipeline carries water in a streamline flow. At a point along the pipe, where the cross- sectional area is `10cm^2`, the water velocity is `1ms^-1` and the pressure is 2000 Pa. The pressure of water at another point where the cross-sectional area is `5cm^2`, is........Pa. (Density of water `=10^3kg.m^-3`)

Options

A. 200 Pa
B. 400 Pa
C. 500 Pa
D. 800 Pa

Answer

C

Explanation

Since cross-sectional area is halved, therefore velocity is doubled.
Now, `p_(1)=2000 Pa, v_(1)=1ms^(-1)`
`impliesp_(2)=?,v_(2)=2ms^(-1)`
Again, `p_(2)+(1)/(2)xx1000xx2xx2`
`=2000+(1)/(2)xx1000xx1xx1`
or `p_(2)=2000+500(1-4)=500Pa`