Let a wire be suspended from the ceiling (rigid support) and stretched by a weight $$W$$ attached at its free end. The longitudinal stress at any point of cross-sectional area $$A$$ of the wire is :

Two copper vessels A and B have the same base area but of different shapes. A takes twice the volume of water as that B requires to fill upto a particular common height. Then the correct statement among the following is :

The terminal velocity of a copper ball of radius 5 mm falling through a tank of oil at room temperature is 10 cm s^$$-$$1. If the viscosity of oil at room temperature is 0.9 kg m^$$-$$1 s^$$-$$1, the viscous drag force is :

A spherical ball is dropped in a long column of a highly viscous liquid. The curve in the graph shown, which represents the speed of the ball (v) as a function of time (t) is