A capillary tube of 2 mm diameter and 20 cm long is fitted horizontally to a vessel kept full of alcohol of density `0.8 g//cm^(3)`. The depth of the centre of capillary tube below the free surface of alcohol is 30 cm. If viscosity of alchole is 0.112 poise, find the amount that will flow in 5 minutes.

Explanation

Here, `r= 1 mm=0.1 cm , l=20 cm`,
`rho = 0.8 g//cm^(3) , h=30 cm , eta = 0.12 poise`
Volume of the alcohol that will be flowing per second through the capillary tube is
`V= (pi P r^(4))/(8 eta l) = (pi h rho g r^(4))/(8 eta l)`
`= 22/7 xx (30 xx 0.8 xx980 xx (0.1)^(4))/(8 xx 0.12 xx 20) = 0.385 c c//s`
Volume flowing out in 5 minutes
`= 0.385 xx 300 = 115.5 c c`
Mass of the liquid flowing out in 5 minutes
`= 115.5 xx 0.8 = 92.4 g`.