Model Rockets

We find places out in the country where there are no buildings or trees for at least 5-6 blocks around. Favorite places are where land has been cleared for building on , but building has not yet started.

3rd law of force by newton.every action has an equal and opposite reaction well there is a combustion chamber in the rocket where fuel and gases are burnt using liquid oxygen.they are thrown out of the rocket with tremendous force and they equally and in the opposite direction push the rocket ahead

You can have different kinds of ways to make a rocket fly. you an use a pump to pump the rocket up into the air, put a antacid tablet to make it fly

because they don't need anymore than three fins to keep them on straight course

Generally unguided rockets used as weapons do not travel as far as missiles, which is the term for guided weapons. Rockets used as fireworks only travel a few hundred feet vertically. Model rockets may reach a height of a mile or more. Rockets used to launch satellites propel the payload above the atmosphere, which expends most of their fuel.

it starts with the pelvic thrust then erection and then boom goes the dynamite

Usually something that will burn hot and hard enough so that the expanding gasses will provide thrust enough to get the rocket airborne.

Model rockets launch by sliding up a rod/wire that is pointing toward the sky. A launch lug is a small tube (like a drinking straw on a small rocket) glued to the side of the rocket body. You slide the small tube (launch lug) down on the rod. The launch lug and rod guide the rocket to start it in the correct direction until it gets going fast enough that the fins can stabilize it.

Visit the links below. The first picture shows a rocket on the rod. It's a little hard to see but the rod goes through the launch lug. At the very beginning of the second link, they are sliding a large rocket lugs onto the rod.

When designing a pop bottle rocket, your objectives are to minimize weight and drag.

Think of the pressure in the bottle as a fixed ammount of energy that will be turned into velocity of the rocket per Energy = 1/2 * Mass * Velocity^2. As your rocket flies up into the sky, two things will happen to that energy. First, the energy will change into potential energy per Energy = Height * Mass * Gravity. (Gravity = the rate of acceleration due to gravity = 9.8 meters / second^s.) Second, the energy will be lost to friction. As your rocket flies through the air, it will bump trillions of trillions of air molecules and give its kinetic energy to them.

To minimize this bumping, you want to make it easy for the rocket to push the air molecules out of the way. This would be best accomplished by a long, slowly tapering nose-cone. Keep in mind that the heavier your nose cone, the less velocity you get.

It depends on what the original model was. If the original model was 100 inches, then a 1/50th scale would be 2 inches.

You can strt by first constructing the rocket body. Using a sheet of computer paper build the body of the rocket and fold it half lengthwise. Cut the paper in half as folded and then take one half and fold it further in half, do it cross wise.

Now you should have one half of the original sheet along with two quarters of it. Fold one of the quarters to half and fold in half one more time but diagnally. Cut along the creases which is created from the folding in order to create four triangles which can be used for the fins. Now you have to take the other quarter and draw a circle on it. Cut it out and mark its center. Sketch two lines which should form a right angle from that point. Cut out the portion marked by those lines and make a cone out of it. Next, take the half of the paper and tape it around the canister. You need to place the canister along one of the edge of the paper and make sure that the opening of the canister should point outside of the cylinder formed by the paper. Now, tape the fins on the part of the cylinder paper which is near to the canister while tape the cone on the other end.

Hope this helps.

Obviously, you want your rocket to fin to have the most effect while minimizing drag.

IM ASSUMING YOUR USING A 1 LITRE SODA BOTTLE

4 fins are usually the most efficient. you want them slender and long, extending past the thrusting end of the bottle. for width, i made mine 30 degrees from straight down, 6 inches long, and tapered. and it worked fairly well. instead of a launch tube, i used a guide rod. i got a pair of four foot steel rods that were thin but strong. on the sides of the bottle i taped straws.

here is a good picture for an example of fins. also has good info about center of mass and stuff

good luck

-jd

http://www.google.com/imgres?imgurl=http://www.seeds2lrn.com/RocketDesign.gif&imgrefurl=http://www.seeds2lrn.com/rocketSoftware.html&h=415&w=519&sz=33&tbnid=QCQhkMzEjGkgGM:&tbnh=105&tbnw=131&prev=/images%3Fq%3Dwater%2Brockets&usg=__HeEWtS6iR89_LAbPH-VZnRG1r9k=&ei=9HxZSrjTNI6uMK2i_UI&sa=X&oi=image_result&resnum=6&ct=image

The smaller it's maximum cross-sectional area in the direction of flight, the faster it goes, as this reduces wind resistance..

Incredibly ! -In rocket flight streamlining is the single most important factor.

A water rocket should probably have three to four fins.

because if thay are in the wrong place the rocket will not be stable

I can not think of any reason you would want to do that? RICE is the key... Rest, Ice, Compress i.e ace wrap, Elevate.

In a real rocket, there is short a time in atmosphere and the aerodynamics are less important. In a model rocket, all flight in the atmosphere and the aerodynamics are very important. In a real rocket, it has a liquid or solid rocket engine and a large propellant mass fraction. In a model rocket, it has a solid rocket engine and a small propellant mass fraction . In a real rocket, there are four forces during atmospheric flight. In a model rocket, there are four forces throughout flight. In a real rocket, there is a long powered flight . In a model rocket, it has a very short powered flight . In a real rocket, it has passive stability and active control . In a model rocket, it has passive stability and no control. In a real rocket, it has expensive materials such as aluminum, titanium, and nickel alloy. In a model rocket, it has inexpensive materials such as balsa, cardboard, and plastic. In a real model, there is a high speed and the heating is very important. In a model rocket there is low speed and the heating is not important.

The C6 -3 is twice as strong as the B6-4 but runs for a shorter time. It will propel a bigger rocket. I use C6 on rockets about 30-33 inches long, 1 inch diam.

Normally model rockets are made from kits you buy at a hobby store. The most famous maker of model rocket kits is a company named Estes. Visit links below.

The other option is to build it from scratch. One great way to build from scratch is to purchase the Designer's Special from Estes. It contains an assortment of body tubes, nose cones, and centering rings. Just make sure to use an 18mm. diameter tube for the engine (usually will need to be 2.5in long) and that the Center of Gravity of the Rocket is at least one body diameter ahead of the Center of Pressure and you'll be fine. You can find the Center of Gravity by balancing the rocket with everything in it, and you can find the Center of Pressure of the rocket by balancing a cardboard silhouette of your rocket, or you can find both before you build the rocket by using a simulator like Rocket Modeler II (http://www.grc.nasa.gov/WWW/k-12/rocket/rktsim.html) or RockSim (http://www.apogeerockets.com/rocksim.asp).

Because the fins and motor thrust make it go up, if aimed up.

Primarily there are two types of fuels used in most rockets today. The space shuttle, at liftoff, uses both. Solid fuel and liquid fuel. Solid fuel rockets are much like the bottle rockets you can buy in a fireworks store. Once they are lit, the burn all of the fuel available and then burn out. The 2 white rockets on the side of the orange tank holding the space shuttle are Solid Rocket Boosters. The large orange tank that holds the space shuttle is full of liquid full that the shuttle uses as it lifts off into space. That fuel is actually liquid.