Water is flowing through a horizontal tube of non-uniform cross-section. At a place, the radius of the tube is `1.0cm` and the velocity of water is `2m//s`. What will be the velocity of water where the radius of the pipe is `2.0 cm`?

Explanation

Using equation of continuity, `A_(1)v_(1)=A_(2)v_(2)`
`v_(2)=(A_(1)/(A_(2)))v_(1)`
or, `v_(2)=((pi r_(1)^(2))/(pi r_(2)^(2))) v_(1)=(r_(1)/(r_(2)))^(2) v_(1)`
Substituting the values, we get `v_(2)=((1.0xx10^(-2))/(2.0xx10^(-2)))^(2) (2)`
`v_(2)=0.5m//s`.