9.1.6. Summary

In the last class as you know it, we discussed about fluid at rest. That is what I will have a recap. Then I will talk about the manometers. And then we will talk about differential manometer. And I will give you a very interesting examples of the stepped well, which was designed long back by ancient architecture and how they have designed the stepped well and that what we will discuss it. Then we will have the applications of hydrostatics that to find out the forces on the submerged surfaces and we will have the summary of this.

In this chunk, we are reminded of the previous lesson focused on fluid statics, which is the study of fluids at rest. The speaker emphasizes that the discussion will evolve to practical applications, notably the use of manometers for measuring pressure. A historical example will also be provided involving stepped wells, illustrating how ancient civilizations ingeniously designed these structures for water storage. Finally, the chunk indicates that there will be a summary concerning the forces acting on submerged surfaces, tying together the application of hydrostatics.

Think of fluid statics as understanding how water behaves in a calm pond. Just like when you drop a pebble and see the ripples, fluid statics explains the calm, still conditions before or after something disrupts the surface. The manometer analogy can be likened to using a straw to measure how deep a drink is in a glass—by observing the height of the liquid in the straw, you get a sense of the pressure pushing the liquid up against gravity.

Now let us come to the manometer. Very simple devices are used to measure the pressure like you have a, let have these type of conduit, the pipes the carrying any liquids and you want to measure it what could be the pressure on that pipe. So we can just insert the tubes like you can see can have the tube like this or can have a tube like this with inclined and all or you can have a inclined like this. So each one having the merit and also disadvantages, like for examples, the manometer is simple device that is what use a liquid column to measure the pressure between two points.

Manometers are essential instruments used for measuring the pressure in fluids, particularly in pipes that carry liquids. They consist of tubes that can be arranged vertically or inclined to capture the pressure readings. The simplicity of the manometer allows intuitive measurements via the height of a liquid column, indicating the difference between two pressure points in a confined space. Each type of arrangement (vertical, inclined) has unique benefits and limitations, affecting their accuracy and usability for different applications.

Imagine your favorite sports drink bottle. When you squeeze the bottle, the liquid rises through the straw. A manometer works similarly; when you measure how high the liquid rises in the straw due to either the squeezing (pressure difference) or atmospheric conditions, you can tell how much pressure was applied. The inclined manometer might amplify the measurement like using a long straw, making it easier to drink from without much effort.

Now there is another type of manometer which is called the differential manometers. As the name says that here, we do not measure a particular point pressure measurements where you consider two points. Because many of our applications, we are not worried about absolute pressure. Mostly we are looking for the two points like I have the pipe and I have the point A and B. So this is a pipe flow, I have the point A and B. At this A and B locations, I want to know it what is the pressure difference between these two point of A and B in this pipe flow.

Differential manometers are specialized devices for measuring the pressure difference between two points in a fluid system rather than measuring absolute pressure at any one location. This is particularly useful in scenarios where the difference in pressure drives the flow within a pipe system. By connecting the manometer to two different points (A and B) in a pipeline, operators can ascertain how much pressure is pushing the fluid from one point to another, allowing for effective monitoring and management of fluid systems.

Think of driving a car. You don't just care about how much gas is in the tank (absolute pressure); you're more interested in how quickly the gas is used as you accelerate. Differential manometers help understand the 'acceleration' of fluid by showing the difference in 'fuel' pressure at two points, crucial for maintaining a smooth flow in piping systems.

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