Calculate the terminal velocity with which an air bubble of diameter 0.8 mm rises in a liquid of viscosity `0.250 Ns//m^(2)` and density `0.95 x 10^(3) kg//m^(3)`. Density of air is` 1.3 kg//m^(3)`

Explanation

` " " a= 0.4 xx 10 ^(-3) m, sigma = 0.95 xx 10 ^(3) = 950 kg//m^(3) ,rho =1.3 kg//m^(3)`
`" " eta = 0.250 Ns//m^(2) , " " v= ? `
` " " v= (2(rho -sigma) a^(2)g)/( 9 eta) = ( 2xx (1.3 - 950 )xx(0.4 xx 10 ^(-3))^(2))/( 9xx 0.250 ) `
` " " = - 0. 135 xx 10^(-3) m//s`