In a draining experiment

PHYSICS · Single correct · CBSE · Physics · Mechanical Properties of Fluids · Mechanical Properties of Fluids

Problem

In a draining experiment, the depth of water above a small exit hole decreases from

0.40\,\text{m}

0.10\,\text{m}

. Neglecting viscosity, which statement best describes how the instantaneous mass flow rate

\dot m

through the hole changes over this interval? (a)

\dot m

becomes one–quarter its original value because exit speed is directly proportional to depth. (b)

\dot m

doubles because the pressure difference between the surface and the hole increases as the tank empties. (c)

\dot m

becomes one–half its original value because exit speed depends on the square root of depth. (d)

\dot m

remains constant because the density of the fluid does not change.