Question

The cubical container ABCDEFGH which is completely filled with an ideal (non viscous and incompressible) fluid, moves in a gravity free space with a acceleration of $a=a_0(\hat{i}-\hat{j}+\hat{k})$ where $a_0$ is a positive constant. Then the only point in the container where pressure can be zero is :

• A. $B$
• B. $C$
• C. $E$
• D. $H$

Answer 1

The correct option is D $H$

Acceleration of fluid $\overrightarrow{a}=a_0(\hat{i}-\hat{j}+\hat{k})$

For pressure at any point on the boundary to be zero, there must be a counter force in opposite direction to the acceleration of fluid.

Thus if $(-\overrightarrow{a})$ at any point at the surface is snclosed completely inside the fluid container, pressure at that point can be zero.

Thus only at point H it is possible.

$\therefore$ Answer$\equiv H$