Studying the Bernoulli Principle

Have you ever wondered how airplanes stay up and what allows them to fly at such high altitudes? The Bernoulli Principle allows us to figure that out. An airplane gets its lift from the Bernoulli Principle. The Bernoulli Principle is the aerodynamic Principle that allows movements to be controlled when included by the wind. Bernoulli's Principle is important in all types of physics and science, it states “as the velocity of a fluid increases, the pressure exerted by the force decreases.

In practical terms, it means that a slow-flowing fluid exerting more pressure than a fast flowing fluid, this means that in slow-moving fluid pressure and velocity are inversely proportional, so if the pressure is high then the velocity is low if the pressure is low then the velocity is high. This explains the reason while taking a shower the shower curtain tends to stick onto you or flow towards you, this is because the fast-moving water flowing from the shower creates an area of low pressure, this causes the shower curtain in the area of low pressure to stick towards the closest area. This Principle also applies to airflow one of the most dramatic everyday examples of this Principle is airplanes.

 This allows airplanes to stay in the air lower pressure caused by the increase of speed of air over the wings the area of pressure under the wings is higher than the pressure above it this makes the wing pushed upwards, and allowing the plane to stay in the air. Air moves faster on the upper surface which causes the air pressure to decrease the lower air pressure over the top of the wing gives it lift. Flying birds use this Principle all the time to allow them to hunt, mate, or fly away. The Bernoulli Principle allows the birds to fly and stay aloft. Birds have a natural curve in their wings and allow them to have this effect given to them. 

Humans can use biomimicry to help design better airplanes to become more efficient based on what the needs are for. We can make a model demonstrating the Bernoulli Principle in many ways, one of the ways we can use to demonstrate Bernoulli’s Principle is by using a hairdryer and a ping pong ball. The hairdryer is our source of wind and the ping pong ball is used because one, it is lightweight and easy to demonstrate how lift must be stronger than its weight and two, it is easily accessible. 

The speed of the wind is creating a difference of pressure which high pressure equals low velocity and low pressure equals high velocity. So it makes the ball fly around or as others would say it hovers. We can identify the Bernoulli Principle taking effect by showing what happens when it takes place. We notice there is a spin on the ball and the ball is bouncing around as though there is a field were it moves around. The ball is confined to that area and because of the area of low pressure and the area of high pressure around it and it causes it to be pulled towards the middle and give it a floating effect. Now, what can we document? To document this info we can make a graph and see if a difference in space between the objects influences the effect it gives to how high or lows the ping pong ball goes.

 There are many ways we can give this experiment a twist. Another way to perform this experiment is to tie two strings onto two different cans and hang them up by the two strings. We can then use the same blow dryer to blow wind and the cans will pull together because of the different pressures in the air. This also shows how when there is a difference between high and low pressure in the air the high-pressure air moves to the low-pressure air creating some sort of magnet. To conduct my experiment I will be using cans and a hairdryer. I will hang the cans using string and I will tape the string to a doorway then I will make a graph recording my data. I will start out with 12 centimeters in between the string I will then grab my stopwatch and see how long it takes for the two cans to touch. I will do this 5 times to get the mean.

 Then, move it each time 1 more centimeter so it should end up at 13 centimeters apart, I will continue to do this until there is no more room for the wind to blow onto and no movement is detected. I will then try and find out any imperfections. Then I will correct them and improve my tests then I will add variation, and determine if the variations have any effect on the experiment or if the Principle is even still in play. Then I will see if there is a difference if I use a different temperature and I will record the data.

 Throughout the experiment I hypothesis that the Bernoulli Principal will work until a point and then immediately stop working after that. I hypothesize this because there are no other variables in the experiment. The only thing that is changing is the distance between the cans. All in all the Bernoulli Principle is an important part of our daily life from day to day. It plays a great role in transportation and sports and does things that we may have never thought of before. 

 Materials: String, two empty cans, Hairdryer, tape, Stopwatch Get two pieces of string and tie them to the tabs of the two empty soda cans Hang the two empty cans by the strings 12 centimeters apart Turn the hairdryer on and aim in between the two cans (for variation try different temperatures) Time how long it took for the cans to touch and when they do stop the stopwatch Record your data on if the cans moved or not Move the cans an centimeter closer together and repeat steps 1-4 RESULTS DISCUSSION My hypothesis for this experiment was that when I moved the cans apart it would work until a point and after that point, it would just stop working completely. As I expected it did stop working after I reached 13 cm. At that point, the cans started moving berserkly and by chance, they hit each other but for consistancy, I still recorded the times they received. I believe this experiment could have been perfected if the cans had a little more weight because I noticed they were moving to fast and not able to gain any momentum to put the Bernoulli principal into play. This model demonstrates how the Bernoulli Principle can attract objects instead of repelling them. The area of high pressure which was the hairdryer was blowing in between the cans caused them to be sucked in because of the area of low pressure surrounding it.

 My results actually impressed me but I wasn't sure if it was going to be as dramatic as I had seen it become. Some possible errors that could have occurred could be that the cans were not the exact same length. Another problem that could have happened is that I noticed the cans did not have the same center of mass and that when I blew the air onto it, they would start to spin around I'm not sure if that was due to the unbalanced can or the wind was causing there to be friction between it caused it to spin. I'm not sure if that made a difference to the experiment in the end though. CONCLUSION Doing this experiment really helped me learn and actually understand what the Bernoulli Principal is. It was not only fun but it allowed me to use my problem-solving skills. One of the first problems that came up was that tying the string to the cans was tedious and it kept sliding off. All in all the Bernoulli Principal is a really fascinating subject to cover from Aerospace engineering to Plane designing for all the different needs that humans desire from making jets faster to making planes more efficient. The Bernoulli Principal was here before us and was only discovered until the 1700s. 

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