Chapter 1, Problem 1.7E

Interpretation Introduction

Interpretation:

Referring to the previous exercise (1.6): without special pressurized equipment, the maximum pressure difference that can be generated is 1atm or 101325 pascals. Height of column of water this pressure difference can support is to be calculated. The approximate height in feet is also be calculated.

Concept introduction:

Pressure can be defined as a force acting on per unit area i.e.,

P = F/A,

Where, F = force,

A = area on which the force is acted.

Pressure can be conveniently measured for gases and fluids. The pressure of a liquid or a gas is equal to the density of that liquid multiplied by the acceleration due to gravity and the height of the liquid above the certain point. The standard unit for pressure is Pascal (Pa). Other units of pressure, such as pounds per square inch and bar, are also commonly used. The pressure units can also be expressed in grams-force or kilograms-force per square centimeter, without properly identifying the force units. The standard atmosphere (atm) is approximately equal to typical air pressure at earth mean sea level and is having the value of 101325 Pa. Since, Pressure is most prevalently measured by its tendency to displace a column of liquid in a manometer, it is also expressed as depth of a fluid. For example: Centimeters of water (or) millimeters of mercury.