DAY 8 – DAW January

Elasticity, Hooke’s law and elastic constants of isotropic solids and their inter-relation;


Q 1. State and explain stokes’ law. A drop of water of radius 0.01 m is falling through a medium whose density is  1.21kg/m31.21 kg/m^3 and η=1.8×105Ns/m\eta= 1.8\times 10^{-5}N-s/m  . Find the terminal velocity of the drop of water. [15 marks]

Q 2. A capillary tube having 1.0 mm diameter, 20 cm in length is fitted horizontally to a vessel in which alcohol is kept fully up to the neck. Density of alcohol is 8×102kg/m38\times10^2kg/m^3  . The depth of the centre of the capillary tube below the surface of alcohol is 40 cm. Find the amount of alcohol that will flow out of the capillary tube in 10 minutes. Coefficient of viscosity of alcohol is. 0.0012 Ns/m20.0012\ Ns/m^2. [10 marks]

Video Solution at 11 pm