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How do you make a water rocket stay in the air longer?
What makes a rocket fly farther? Closed Nose – The top of the rocket (the nose or cone) needs to be closed so that no air leaks out. Weight – The rockets fly much better if there is some weight (paper clips, pennies or washers) at the TOP of the rocket, but not too much weight.
How do you make a pop bottle rocket fly farther? If you did Part II, you will have noticed that adding a small amount of water to the bottle causes it to fly much farther.
What makes a rocket fly stable and straight? The aerodynamic shape of the nose cone helps prevent air from slowing the rocket. The fins help guide the rocket to fly straight.
Conclusion. As can be seen from the graphs above the optimum amount of water can greatly vary from 10%-60% depending on your rocket and launcher configuration, however, most rockets will not fall into these extremes. For larger nozzles the optimum is closer to 33% while for smaller nozzles the optimum is closer to 25%.
Three fins are best when designing a high performance, low drag rocket. This allows interference drag (drag caused by interference of the airflow over the body and fins at the junction) to be reduced by 25 percent.
Typically, a water rocket uses a plastic bottle in which the pressurized air, and water, goes in. When the air pressure becomes high enough, the plastic bottle releases and flies high up into the air. The higher the air pressure, the faster the water shoots out, and the greater the “push” force on the rocket.
Before launch, the bottle is filled with some amount of water, which acts as the “propellant” for the launch. Since water is about 100 times heavier than air, the expelled water produces more thrust than compressed air alone. The mass of the bottle rocket varies during the flight because of the exhausting water plume.
Making a rocket as narrow as possible is the best way to reduce drag. The speed of a rocket through the air similarly increases drag. As speed doubles, drag increases four times as much.
The lift of a rocket is a side force used to stabilize and control the direction of flight. Lift occurs when a flow of gas is turned by a solid object. This source of drag depends on the shape of the rocket and is called form drag. As air flows around a body, the local velocity and pressure are changed.
A launch angle of 45 degrees maximizes the range (see the figure below). When a projectile is launched, it has both a vertical velocity and a horizontal velocity. (NOTE: If the wind velocity is high and coming from behind, then the rocket may go further if the angle is increased above 45 degrees.
Even with no weight of water inside the bottle, the bottle rocket will still fly upwards. Thsi is because the air in the bottle has a mass so when it is pushed downwards there is still an equal and opposite reaction pushing back up. The air being pushed downwards also produces an upward force on the rocket.
Stop! All fins must be at least 10 cm from the throat exit plane of the bottle see diagram 1.
If the rocket wobbles, or the tail points in the direction of rotation, the rocket is unstable. You can increase the stability by lowering the center of pressure, increasing the fin area, for example, or by raising the center of gravity, adding weight to the nose.
Being unstable in a rocket design is bad. Being over-stable is not bad. It basically means that the rocket will have a greater tendency to weathercock if there is any wind at launch. You can play with this in RockSim by creating a long rocket with big fins.
The definition for model rocket stability is when the Center-of-Gravity (CG) is in front of the Center-of-Pressure (CP). The further dis- tance the CG is in front of the CP, the more stable the rocket will be. “Stability” for us essentially means to fly a predictable flight path.
To make rocket fuel, start by mixing potassium nitrate and sugar in a container. Then, transfer the mixture to a saucepan and add some Karo syrup and water. Next, heat the ingredients over medium heat for 5 minutes, stirring it constantly as it thickens.
The cap of the bottle must be drilled to produce a nozzle for the rocket. Do not make the nozzle hole smaller than 3/8 inch because this can produce excessive pressure in the bottle during combustion resulting in explosion of the bottle. Use only rubbing alcohol (isopropyl alcohol) for the fuel.
A: The simple answer is something less than half full. Since the compressed air stores the energy, and the water provides momentum, both are needed. Fill perhaps 40-50% of the motor volume with water. We call this the Load Fraction.
Theoretically, the best fin shape for a rocket is an “elliptical fin shape.”
Measure the nose cone from its base (right where it starts to narrow) to its tip and record the length in your data log and on the rocket itself. Once completed, the rocket will be about 13 cm (about 5 inches) tall.
A nose cone is the conically shaped forwardmost section of a rocket, guided missile or aircraft, designed to modulate oncoming airflow behaviors and minimize aerodynamic drag.
1st Law – A rocket will remain on the launch pad until an unbalanced force is exerted, propelling the rocket upward. 3rd Law – Finally, the action force of the air (and water) as it rushes out of the nozzle creates an equal and opposite reaction force propelling the rocket upward.
Modern space rockets have main engines powered by a liquid fuel (such as liquid hydrogen) and liquid oxygen (which does the same job as the air sucked into a car engine) that are pumped in from huge tanks.
ballast Add to list Share. A ballast is any heavy material that helps to make a ship or plane stable, including metaphorical ships like your mood. A weight on the bottom of a rocket might act as ballast to help it glide straight.