Water is moving with a speed of `5.18 ms^(-1)` through a pipe with a cross-sectional area of `4.20 cm^2`. The water gradually descends `9.66 m` as the pipe increase in area to `7.60 cm^2`. The speed of flow at the lower level is

Options

A. `2.86 ms^(-1)`
B. `3.0 ms^(-1)`
C. `3.82 ms^(-1)`
D. `5.7 ms^(-1)`

Answer

A

Explanation

From the principle of continuity, `A_(1)v_(1)=A_(2)v_(2)`
`v_(2)=(A_(1)v_(1))/(A_(2))=(4.20xx5.18)/(7.60)=2.86ms^(-1)`