Essay On Bernoulli Equation

Chan Hoi Yiu

Comment on the validity of the Bernoulli equation for:

 Convergent flow

According to the experiment results, the smaller the diameter of the duct, the higher the velocity of the fluid, resulting in a higher dynamic head and lower static head. This validates the Bernoulli equation.

 Divergent flow

For the divergent flow, the apparatus is placed in a revised manner. According to the experiment results, the higher the dynamic head, the lower the static head.

Therefore, it also validates the Bernoulli equation.

State clearly the assumptions made in deriving the Bernoulli equation and justifications for all your comments.

1. The fluid is assumed to be incompressible that when pressure changes, the density of the fluid remains constant.

It is assumed that there is no air bubble in the setup.

Causes of errors and ways of improvement

There are some sources of error affecting the experiment results and the corresponding ways of improvement.

1. Energy loss due to friction of measuring equipment

As the fluid is not frictionless in reality, there is energy loss due to friction between the fluid and the measuring equipment.

The fluid may collide with the measuring equipment and even splash out of the container. The system should be fully closed, reducing the fluid slashed out as well as the energy loss.

2. Air bubble in the setup.

If there is air bubbles in the setup, the accuracy of the water collected is affected.

To improve, the pumping out of air bubble can take a longer time. Also, twisting the tube helps pumping out the air bubbles.

3. Inaccuracy of taking reading of measurement.

Any measure is just estimation and there should be inaccuracy. In order to increase the accuracy of the measurement, machines can be used instead of taking measurement by human. For example, machine can be used to detect the water level in the manometer instead of judging by human eyes. We can also assign more people to take the reading and take the average to increase the reliability of the

The top of the plane wing is curved while its bottom is completely flat. Flying in the sky, air travels concurrently across both the top and the bottom of the wings. This design allows the air at the bottom of the wings to move slower, creates a higher pressure at the bottom. It also allows the air on top of the wings move faster and creates a lower pressure. Therefore, the airplane is supported by the higher pressure at the bottom, helping it to move upward in the