How much fuel does a rocket need?
477827
All depends on how far you want the rocket to go and how much mass you want to get there. Missiles use rocket engines too; they don't need much fuel and are mostly solid fuelled.\n\nA standard Ariane 5 puts up 6.7 tonnes into geostationary orbit and uses two solid rocket boosters with 237.8 tonnes of solid fuel in, one main liquid fuel rocket engine burning 132.27 tonnes of liquid oxygen and 25.84 tonnes of liquid hydrogen and an upper stage burning 9.7 tonnes of Hydrazine / N2O2. Other slightly more powerful versions can put 9.6 tonnes into geostationary orbit.
1035230
First of all, it depends on what you need the thruster for. Chemical rockets (solid, liquid, and hybrid) are the only ones with strong enough thrust to get off the Earth, but once you're in orbit even a low continuous thrust will get you where you want to go, if you have the time.\n\nChemical rockets combine fuel and oxidizer to create thrust. Liquid and solid fueled rockets are just what they sound like; hybrids use a solid fuel but a liquid oxidizer to to start and stop the burn. This helps to deal with one of the biggest problems with solid fuel rockets - once they're lit, they can't be shut off. A hybrid can be throttled off just by stopping the flow of oxidizer.\n\nHall effect and ion thrusters are a bit different. They use a fuel (typically a light gas, but there's a particular type that uses solid Teflon) that is ionized and then passed through a magnetic field to accelerate it to very high speeds. The drawback is that the acceleration is very low, so it can't be used to launch off the Earth. The plus is that you don't really need the high thrust of a chemical rocket in space - it just takes you longer to get anywhere. There was a British spacecraft that went from Earth orbit to the Moon using only ion thrusters; it took eighteen months!
767660
A rocket is subjected to four forces in flight; weight, thrust, and the aerodynamic forces, lift and drag.\n\nat rest I will denote the launch pressure by the symbol ps. The pressure exerts an equal force on all sides of the pressure vessel, the cone of the engine. Because the rocket is free to move along the launch mechisims, the pressure exerts a vertical force given by: \n\nFp = (ps - po) * A \n\nwhere Fp is the pressure force, po is the atmospheric pressure, and A is the cross-sectional area of the rocket tube. The net force acting on the rocket is the difference of the vertical pressure force and the weight W of the rocket: \n\nFnet = (ps - po) * A - W \n\nTo simplify the analysis, we are going to assume that the length of the launch tube is small relative to the length of the rocket. As the rocket moves, the pressure remains fairly constant inside the tube. In reality, there is a slight decrease in pressure as the volume increase, but we are going to neglect that effect to simplify this analysis. With a constant pressure, and constant pressure force, we can use a simple algebraic form of Newton's second law to determine the acceleration a, velocity v and the distance y which the rocket moves along the launch tube: \n\nFnet = m * a \n\nm * a = (ps - po) * A - W \n\nwhere m is the mass of the rocket This equation can also be written as: \n\nW * a = g * ((ps - po) * A - W) \n\nwhere g is the gravitational acceleration, which is equal to 32.2 ft/sec^2 or 9.8 m/sec^2 on the surface of the Earth. The value of g is different on the Moon, and on Mars. The weight W is equal to the mass times the gravitational acceleration. Now divide both sides by the weight to determine the rocket acceleration along the launch tube: \n\na = g * ((ps - po) * A / W - 1) \n\nFor a constant acceleration, the velocity v and distance traveled y are given by: \n\nv = a * t \n\ny = .5 * a * t^2 \n\nwhere t is the time. Using the length of the launch tube L, we can now solve for the lift off time - TLO by using the second equation: \n\nTLO = sqrt (2 * L / a) \n\nand then using this time, we can use the first equation to solve for the velocity at the end of the tube: \n\nv = TLO * a \n\nv = sqrt ( 2 * L * a) \n\nAs the rocket clears the end of the launch tube (t = TLO+), the air inside the rocket, at pressure ps, will rush out the exit and the pressure will equalize with free stream inside the tube. In reality, this will provide an additional amount of thrust T given by: \n\nT = m dot * Ve \n\nwhere m dot is the air mass flow rate out of the tube, Ve is the exit velocity of the air. For an air rocket, with no nozzle and small volume, this additional thrust is small relative to the weight of the rocket, and we will ignore this effect. \n\nThe velocity v at the end of the launch tube is used as the initial velocity in the flight equations to determine the flight trajectory of a rocket.
448983
when you have complex machines, especially ones with rocket fuel, things on ocassion fail, they still do, rockets blow up every year. the trick is to minimize the failure through better design and materials and manufacturing. MIKE
372374
You didn't specify the fuel but in general burning is a chemical reaction with oxygen or an oxidation process.  This process releases energy in some form.  Heat is one of those forms, mechanical motion, and light are others.\n\nThere is no requirement for carbon in the process of burning fuel as is stated by some other answerer's.  Let's, for example, consider burning hydrogen.  The hydrogen combines with the oxygen (oxidizes) which releases energy in the form of heat.  The Hindenburg disaster had very little carbon in its primary burn.\n\nSince this combining of 2 or more elements seems to be a requirement for burning (at least one of them being oxygen) it is possible to un-combine them by adding energy to revert to the initial elements.  Again for simplicity, let's use hydrogen and oxygen [so abundant on this planet].  When the hydrogen and oxygen are burned in proper balanced proportions (two atoms of hydrogen to one oxygen in stoichiometric proportions) there is only water and energy.  The energy we use to move things, light things, heat things, etc.  The water in this case is waste.  You can perform electrolysis on the water and separate the O2 and H2. You can then burn them again releasing the energy that you put back into the separation through electrolysis.  This is just un-burning the hydrogen and oxygen by adding energy.\n\nTypically one thinks of burning as a non-reversable process but only when you're talking about proteins...like un-frying an egg.  \n\nA string of hydrocarbons burned with "air" is also more complicated because we're using a large percentage of nitrogen along with our oxygen.  The ratio is roughly 80/20 Nitrogen to Oxygen. To maintain the balance of equations (that stoichiometric word) we'd be working with nitrogen oxides (burned nitrogen) like nitric oxide and nitrogen dioxide and many carbon by-products like carbon monoxide and carbon dioxide.\n\nAll in all it's a big mess.\n\nI hope that fully answered your question.
395571
http://en.wikipedia.org/wiki/Category:Rocketry
713495
Wouldn't it depend on the size of your rocket?
268556
no....\n\nit wont need fuel..... it is moving in the space only through the gravitional force...
905696
A solid propellant rocket has a solid fuel core, for example gunpowder. A liquid propellant rocket, such as an ICBM, has liquid for fuel, like gas (but a specialized fuel more developed than gas).\n\nA rocket with solid fuel can only go a short distance. Liquid fuel is used more for missiles that have a long way to go and can be guided (intelligent).
33021
The most important thing right now is that it can be used as fuel. It is much cheaper than gas and also does not cause pollution. We have used it as rocket fuel for years but only recently have we developed vehicles that can run on it. They are in California.
973514
Pollution caused by space launches:\n\nThe magnitude of space launch combustion products can be illustrated by a \ncomparison of the amount of fuel consumed by a  space shuttle launch with \nthe amount of gasoline consumed in the United States in one day:\n\nSpace shuttle fuel consumed in a launch:  3.5 million pounds\nGasoline consumed in one day in the US - 2,500 million pounds\nIn other words, one space shuttle launch is equivalent to about two minutes \nof gasoline consumption in the United States.\n\nThere were 78 space launches worldwide in 1999, almost all much smaller \nthan the space shuttle.\n\nThe pollution caused by space launches depends not only on the total \nquantity of the fuels used, but on their chemical composition..\n\n Propellants used for powering space launches are of four types:\n\n1. Solid  - Propellants that are a mixture of solid chemicals - a fuel and \nan oxidizer - that burn at a rapid rate when ignited, expelling hot gasses \nfrom a nozzle to achieve thrust. Fireworks are an example of the use of \nthis kind of propellant. The combustion products depend on the chemicals \nused. The space shuttle uses potassium perchlorate (KClO4) and powdered \naluminum. The combustion products are  potassium chloride and aluminum \noxide  \n\n2. Cryogenic - In space propellants, this refers to liquid hydrogen (LH) \nand liquid oxygen (LOX), which burn when mixed and ignited. LOX is a liquid \nbelow -298 degrees F and LH is a liquid below  -423 degrees F. They are \nstored in the space vehicle in insulated tanks and pumped into the rocket \nengines where they burn to expel hot gases.  The LOX/LH combination is by \nfar the most efficient in the amount of thrust per pound of fuel.  The \ncombustion product is water vapor.\n\n3. Petroleum - Instead of liquid hydrogen, a purified kerosene is used as \nthe fuel and is mixed with liquid oxygen and burned in the engine. The \ncombustion products are carbon dioxide and water vapor. This fuel system is \nusually used in launches of smaller rockets where the complications of \nhandling liquid hydrogen are not justified. \n\n4. Hypergolic - fuels and oxidants that ignite on contact without an \nignition source.  These are generally used for maneuvering after the soak \nvehicle has reached orbit. The combustion products depend on the chemicals \nused.  The space shuttle uses monomethyl hydrazine (N2CH6) and nitrogen \ntetroxide (N2O4).  The combustion products are nitrogen, water vapor and \ncarbon dioxide.\n\nThe pollution effects of the four types of fuels are:\n\nSolid fuel - The major combustion products of potassium chloride and \naluminum oxide and relatively innocuous.  Potassium chloride is used as a \nfertilizer and has medicinal uses.  Aluminum oxide is an unreactive \ncompound and is used as an abrasive.\n\nCryogenic - The only combustion product of LH/LOX is water.\n\nPetroleum - The combustion products of water and carbon dioxide are \nharmless except of any possible contribution of carbon dioxide to global \nwarming, but the carbon dioxide from this source  would be infinitesimal \ncompared to the energy produced by burning  coal and petroleum\n\nHypergolic - The combustion products of this kind of fuel are not a \npollution problem. In any event this fuel is used only in small quantities \nfor maneuvering.\n\nThe space shuttle uses about 2.3 million pounds of solid propellant in the \nlaunch boosters and about 1.2 million pounds of LH/LOX in the main engines. \nA relatively small amount of hypergolic fuel is used for controlling the \nshuttle once in orbit. Kerosene/LOX propellant is not used.\n\nWith regard to possible effect on the ozone layer, the only combustion \nproduct that would be suspect is the chloride ion of potassium chloride. \nStudies have shown that in contrast to organic chlorine (as in banned \nrefrigerants) inorganic chloride does not persist in the altitudes of the \nozone layer and is not a factor in ozone depletion.
748326
The fuel should increase to take the load. My experience is on turbine generators, one was 9 mega. WATS.
166600
The idea is to add the acid to the water and then pass a current through the water.  The water will split into Hydrogen and Oxygen.  The bubbles of these gasses can collected in tubes, the H will produce twice as much gas as the O.\n\nThe rocket can be powered by igniting the hydrogen.\n\nI think the citric acid is more reactive than absorbic acid, but any thing will do including vinegar (acetic acid).
957293
Rockets go at many different speeds depending on the application. A good example is the speed a rocket needs to go when leaving the earth and going into earth orbit. This is called "escape velocity". For rockets leaving the north pole where the spin of the earth is not a factor, the escape velocity is 11.2 km/sec (approx. 25,000 miles per hour).\n\nOnce out of earth orbit, rockets attached to spacecraft may increase speed to reach distant planets. Speed will stay the same until the rocket is ignited. Once the rocket is burning, the speed will continue to increase. Small rocket engines, like "ion engines", with very low but continuous thrust will keep the rocket accelerating for a very long time.
1035139
how much do you need?
731455
Something that may be fun is a project with model rockets. Give them the necessary information to calculate the height of the rocket, based on the rocket engine and mass of the rocket as homework.\n\nThen at school, fire a few of them and using basic trig calculate the height and see how close they are.\n\nRocket engines are typically rate something like: A8-3 which breaks down as follows:\nA --> 2.50 Newton-seconds of power\n8 --> average thrust (in newtons)\n3 --> seconds from end of thrust to ejection charge (parachute)\n\nThe engines also have a time-thrust curve that shows how the power is delivered over time. Check the following link below for some more info:\n\n------------------------------------------------------------------------\n\nHere is another one:\nNot sure how readily available props are for you but if you can hook up a camera in a room with a strobe light/flash and then set up a collision (air hockey table or pool table come to mind) then you can calculate the velocity of each object, measure its mass and then demonstrate the conservation of momentum using vectors. Because you know the frequency of the strobe, and the distance traveled, you can compute the vector velocity.\n\nOr how about:\nFirst, fire an arrow down a football field. Given the amount of time aloft calculate the initial velocity (ignore air resistance/friction) Then fire an arrow at a bale of hay (extend the bow by the same amount) and measure how far into the bale the arrow went. Using the same initial velocity and distance into bale, calculate the rate of deceleration and coefficient of friction of the hay bale.
767612
You will need to investigate the chemical mixture to use, there are common ones like black powder (Potasium Nitrate [saltpeter] + charcoal + sugar) I used to buy saltpeter at the drug store (in the olden days they gave it to boys to reduce sex cravings...) but I don't know if it is available there anymore...\n\nYou need 2 other components besides the fuel - 1. A nozzle, and 2. An igniter. \n\nThe simplest nozzle would be a straight hole drilled through a plug (that would close the bottom of your cylinder rocket body full of fuel). But a point to point cone shape would be better. Another alternative, I saw a design for a model rocket which used an empty CO2 cartridge (like a BB Gun would use) the cartridge end is very nozzle like and you just fill it with your fuel.\n\nFor the ignitor, there is something called nichrome wire, it is a thin wire that when you attach a battery to it, it gets hot (even easier though, they sell little ignitors at hobby stores for estes type model rockets.) You would have to mount the ignitor into your fuel and plug up any remaining space so that the fuel doesn't fall out...