Question

Write the factors on which pressure at a point in liquid depends on?

Answer 1

The pressure due to a liquid in liquid columns of constant density or at a depth within a substance is represented by the following formula:

where:

p is liquid pressure,

g is gravity at the surface of overlaying material,

ρ is density of liquid,

h is height of liquid column or depth within a substance.

It is important to recognize that the pressure does not depend on the amount of liquid present. Volume is not the important factor – depth is. The average water pressure acting against a dam depends on the average depth of the water and not on the volume of water held back. For example, a wide but shallow lake with a depth of 3 m (10 ft) exerts only half the average pressure that a small 6 m (20 ft) deep pond does (note that the total force applied to the longer dam will be greater, due to the greater total surface area for the pressure to act upon, but for a given 5-foot section of each dam, the 10 ft deep water will apply half the force of 20 ft deep water).

A person will feel the same pressure whether his/her head is dunked a metre beneath the surface of the water in a small pool or to the same depth in the middle of a large lake.

Answer 2

Answer

1. Pressure in a fluid is directly proportional to its height.

2. pressure in a fluid is directly proportional to its density .

3. pressure in a fluid is directly proportional to the acceleration due to gravity.

4. pressure is a fluid is independent of the area of cross section.

5. If $P_A$ pressure due to it atmosphere than the total pressure at point B is $P_A$ + h.p.g