Application and proof of existence of atmospheric pressure or lift pump and low it works

Answer 1

Application and Proof of Existence of Atmospheric Pressure in Lift Pumps

Introduction to Atmospheric Pressure: Atmospheric pressure is the force per unit area exerted by the weight of the atmosphere above a particular point. At sea level, this pressure is approximately 101.3 kPa (kilopascals) or 14.7 psi (pounds per square inch). Atmospheric pressure is crucial in various applications, particularly in pumping systems like lift pumps.

Lift Pump Operation:

Basic Principle: A lift pump operates primarily on the principle of atmospheric pressure and suction. When a liquid is to be lifted from a lower elevation to a higher one using a lift pump, the following steps take place:

1. Vacuum Creation: The pump creates a partial vacuum in the pumping chamber (the area inside the pump where fluid is being sucked). By pushing the piston or using other mechanisms, the pressure inside the pump chamber decreases.

2. Atmospheric Pressure: The atmospheric pressure acting on the surface of the liquid in the source (like a well or a reservoir) is greater than the pressure in the pump chamber. This pressure differential causes the liquid to flow into the pump.

3. Liquid Elevation: Once the liquid enters the pump chamber, the mechanism (like a piston) pushes the liquid upwards through a discharge pipe, overcoming the gravitational force.

4. One-Way Valve: Most lift pumps have a one-way valve (check valve) at the outlet, which prevents the liquid from flowing back down once it has been lifted.

Proof of Existence of Atmospheric Pressure:

Archimedes’ Principle and Barometers: The existence of atmospheric pressure can be demonstrated through simple experiments, like the operation of a barometer:

• A mercury barometer, for example, consists of a glass tube filled with mercury, inverted in a dish of mercury. The mercury remains in the tube, creating a vacuum at the top; the height of the mercury column reflects atmospheric pressure. This column stays at around 760 mm at sea level, representing the balance between atmospheric pressure and the weight of the mercury.

Experiment with a Straw: Another simple demonstration involves using a straw:

1. Place one end of a straw in a glass of water, and cover the top of the straw with your finger.
2. When you lift the straw out of the water while keeping your finger on the top, the water stays inside the straw.

This occurs because your finger creates lower pressure inside the straw compared to the external atmospheric pressure, which pushes the water up into the straw.

Applications of Lift Pumps:

• Water Wells: Lift pumps are often used in agricultural and domestic water supply systems to extract water from wells.
• Irrigation Systems: They are widely used to deliver water from lower reservoirs to agricultural fields.
• Mining: In some mining operations, lift pumps are used to remove groundwater from mines.
• Sumps and Drainage Systems: Lift pumps help clear excess water in basements or low-lying areas.

Conclusion:

The operation of lift pumps relies fundamentally on the principles of atmospheric pressure and suction. By creating a vacuum that reduces pressure within the pump chamber, atmospheric pressure outside the system is leveraged to lift the liquid, demonstrating the practical application of atmospheric pressure in various fields. These principles are well established in fluid mechanics, showcasing the interrelationship between pressure and liquid movement.