A manometer connected to a closed tap reads `4.5 xx 10^(5)` pascal. When the tap is opened the reading of the manometer falls is `4 xx 10^(5)` pascal. Then the velocity of flow of water is

Options

A. 7 m`s^(-1)`
B. 8 m`s^(-1)`
C. 9 m`s^(-1)`
D. 10 m`s^(-1)`

Answer

D

Explanation

For manometer
`(p_1-p_2)/(rho g)=(v^2)/(2g)`
`implies (0.5 xx 10^5)/(10^3)=(v^2)/(2) implies v = 10 m//s`.