An iron sphere of diameter 10 mm falls through a column of oil of density 940 kg//m^(3) . The density of iron is. 7.8 xx 10^(3)kg//m^(3). The coefficient of viscosity of oll is 4.48 Ns//m^(2). Caleulate the terminal velocity attained by the ball.

An iron sphere of diameter 10 mm falls through a column of oil of dens

1.	An iron sphere of diameter 10 mm falls through a column of oil of density 940 kg//m^(3) . The density of iron is. 7.8 xx 10^(3)kg//m^(3). The coefficient of viscosity of oll is 4.48 Ns//m^(2). Caleulate the terminal velocity attained by the ball.
Answer» SOLUTION :Radius of the BAIL = ` a = 5 xx 10 ^(-3) m ` Density of oil `= sigma = 940 kg//m^(3) ` Density of iron sphere = ` rho = 7.8 xx 10 ^(3) kg//m^(3)` Coefficient of viscosity of oil =` eta = 4.78 Ns//m^(2)` Terminal velocity `= V= ? ` ` "" v= (2(rho - sigma)a^(2) g)/( 9eta )= ( 2(7.8 xx 10 ^(3) -940)xx 25xx 10 ^(-6) xx 9.8)/( 9xx 4. 78) ` ` "" = 0.078 m//s `