11.Three capillaries of lengths L, L / 2 and L / 3 are connected in series. Their radii are r, r / 2 and r / 3 respectively. Then if stream line flow is to be maintained and the pressure across the first capillary is P, then

12.A water tank of height 10 m, completely filled with water is placed on a level ground. It has two holes one at 3 m and the other at 7 m from its base. The water ejecting from

13.The rate of flow of a liquid through a capillary tube of radius r is V when the pressure difference across the two ends of the capillary is P. If pressure is increased by 3P and radius is reduced to r / 2, then the rate of flow becomes