We can use the insides and outside pressures to make water come in or out of a container.

When air can’t get into a bottle from a direction while water is trying to flow through the air basically stops it. Why? It is to do with the pressure inside and outside of the bottle of water. The water is pressured by gravity and wants to flow out while the air can only get in through that hole and can’t because water is denser than air and air can only float above water, not get below water, unless not pressured from the top straw being above the bottom straw without our red clog.

When the green straw bottom is below the red straw bottom the air gets pressured by the “falling” water and can’t rise, thus making it impossible for the air to rise and the water to come out of the inclosed container where the air is stopping it from coming out by pressuring it like if there was only one straw, because the air can’t rise up from its position underneath the straw.

Here, the air encounters less resistance, as the water can still flow through the red straw without encountering resistance from below its flow line. This allows the air to bubble up, enabling the water to flow out without much trouble. The air can rise without being too pressured because the water can still flow through, not exerting much pressure on the air while flowing out. This is because the red straw is positioned below the green straw's bottom, allowing the air to safely pass without being obstructed by the water trying to fall upon it. It prevents the air from being stopped from bubbling to the top by having a layer of water below the air that can still flow through the straw.

We use a vacuum pump to suck water out of the second container via the sucktion of air having no choice, but to pull in through the other straw, thus pulling in the water on the other end. This is due to the air being pulled out, causing a vacuum that must be filled by something else, whereas in this case it is the water at the other end because that is the only place more of a liquid can be sucked from to maintain the pressure inside of the bottle of water without imploding or decompressurising and getting a hole punched through by the vacuum trying so desperately to pull in something to fill the gap of nothing.

We can use a pump to start pumping in air and pushing the water through the red straw pushing it into our other container where we collect the water that was pushed out of the our bottle that we have here right now. The air goes in and the water goes out of the bottle due to the pressure inside growing and the need for the water to get out of the bottle to stabilize the pressure inside and maintain the pressure with the outside pressure to stop the bottle from exploding with the force of a miniature bomb.

The presure of the water and the force caused by it. Whether the cap is open or closed. How high the straw is. How tall the water level is.

I designed 4 experiments to test my hypothesis:

Experiment 1:

The cap is closed, there are three holes on the side of the milk container that you see, and the bottle is filled with water to the brim.

The cap is open, there are three holes on the side of the milk container that you see, and the bottle is filled with water to the brim.

Experiment 2:

The green straw bottom is below the lowest point of the red straw and the water is filled to the brim.

The green straw bottom is above the red straw’s highest point.

Experiment 3:

The green straw has a vacuum pump attached to it and it is sucking in the air.

The water level is below the red straw’s lowest point inside the bottle of water and air is getting pumped in.

Experiment 4:

Cap is open and tube is filled with water. Tube bottom is lower than hole.

Experiment 1:

Part 1: The water is trapped and can’t flow out through the three holes.

Part 2: The water is not trapped and can flow out through all the three holes at once.

Experiment 2:

Part 1: The water doesn’t come out of the straw.

Part 2: The water is flowing out rapidly and the air is bubbling upwards to the top.

Experiment 3:

Part 1: The water is coming out of the other container and is raising the water level of our bottle water level.

Part 2: The water is flowing through the red straw from the pumping of air.

Experiment 4:

The water even came out when the water level was lower than the highest point of the tube.

Experiment 1:

Part 1: When air can’t get into a bottle from a direction while water is trying to flow through the air basically stops it. Why? It is to do with the pressure inside and outside of the bottle of water. The water is pressured by gravity and wants to flow out while the air can only get in through that hole and can’t because water is denser than air and air can only float above water, not get below water, unless not pressured from the top straw being above the bottom straw without our red clog.

Part 2: Air can come in to the container from above the three holes and the water can flow out freely because there is no pressure holding it back and the air inside the bottle is in touch with the rest of the air in the atmosphere around us and can freely come in.

Experiment 2:

Part 1: When the green straw bottom is below the red straw bottom the air gets pressured by the “falling” water and can’t rise, thus making it impossible for the air to rise and the water to come out of the inclosed container where the air is stopping it from coming out by pressuring it like if there was only one straw, because the air can’t rise up from its position underneath the straw.

Part 2: Here, the air encounters less resistance, as the water can still flow through the red straw without encountering resistance from below its flow line. This allows the air to bubble up, enabling the water to flow out without much trouble. The air can rise without being too pressured because the water can still flow through, not exerting much pressure on the air while flowing out. This is because the red straw is positioned below the green straw's bottom, allowing the air to safely pass without being obstructed by the water trying to fall upon it. It prevents the air from being stopped from bubbling to the top by having a layer of water below the air that can still flow through the straw.

Experiment 3:

Part 1: We use a vacuum pump to suck water out of the second container via the suction of air having no choice, but to pull in through the other straw, thus pulling in the water on the other end. This is due to the air being pulled out, causing a vacuum that must be filled by something else, whereas in this case it is the water at the other end because that is the only place more of a liquid can be sucked from to maintain the pressure inside of the bottle of water without imploding or decompressurising and getting a hole punched through by the vacuum trying so desperately to pull in something to fill the gap of nothing.

Part 2: We can use a pump to start pumping in air and pushing the water through the red straw pushing it into our other container where we collect the water that was pushed out of the our bottle that we have here right now. The air goes in and the water goes out of the bottle due to the pressure inside growing and the need for the water to get out of the bottle to stabilize the pressure inside and maintain the pressure with the outside pressure to stop the bottle from exploding with the force of a miniature bomb.

Experiment 4:

The tube has no air and the tension of the water molecules bring the rest along with the ones that had already left the system. So, the pressure goes all the way through the pipe.

In conclusion, I learned alot about fluid dynamics throughout doing these experiments. I also learned what PV=nRT is and why it is important.

Here are some applications of fluid dynamics!

Planes and Cars: People who make planes and cars use these ideas to make them go faster and use less fuel. They figure out how air moves over and around them, so they can glide smoothly and quickly.

Weather Watching: Scientists who study the weather use these rules to guess if it's going to rain, be sunny, or if a storm is coming. They look at how air moves and changes in the sky.

Breathing Indoors: When we're inside buildings, there's a special system that uses these rules to keep us warm in winter and cool in summer. It moves air around so we feel comfy.

Playing with Water: Whether it's water coming out of a hose, in a swimming pool, or in a river, these same ideas help us understand how water moves and behaves.

A source of error my experiment might have is tiny gaps in my glue that may release a bit of pressure. Another potential source of error is friction in the tubes but it should be very little.

Walker, J. S. (2017). Physics (third edition). Pearson.

I want to acknowledge my physics teacher for teaching me the physics behind my project.