Question

Which of the following is a correct statement regarding the pressure due to fluids?

• A. Force acting on the wall due to pressure is always perpendicular to it because of collision between the molecules takes place perpendicular to it.
• B. Force acting on the wall due to pressure is always perpendicular to it because of collision between the molecules takes place oblique to it.
• C. Force acting on the wall due to pressure is always oblique to it because of collision between the molecules takes place perpendicular to it.
• D. Force acting on the wall due to pressure is always perpendicular to it because of collision between the molecules takes place at any direction to it but its normal reaction on the wall is always perpendicular to it.

Answer 1

The correct option is D Force acting on the wall due to pressure is always perpendicular to it because of collision between the molecules takes place at any direction to it but its normal reaction on the wall is always perpendicular to it.

The net force acting on a wall of fluid containing vessel is always normal to it because effective force is due to collisions of molecules to the wall of the vessel.