# Tag Info

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Of course it could go much slower spending much more fuel to escape from gravity ! If you look at Ariane 5 speed after 2minutes in the air, it is "only" 2km/s, far from the 11km/s required to leave the Earth's attraction (at ground altitude). It could indeed go much slower, it would just to go much further (if you decrease v, you increase r)

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Any launch profile will suffice (as long as you do not try to go through the Earth of course) as long as the velocity at the end meets the following criteria, $$\|\vec{v}\| \geq \sqrt{\frac{2GM}{\|\vec{r}\|}}$$ where $\vec{r}$ is the radius (position relative to the center of mass of the Earth) at that moment. For this I also assume that its trajectory ...

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You've made the common mistake of thinking that the velocity needed to launch a satellite is the (initial) velocity needed to raise it to its orbital radius. If you raise a satellite to e.g. 300km then let go the satellite will immediately fall straight back to Earth. You need to do two things: raise the satellite to 300km increase its tangential velocity ...

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There are a number of technologies for attaining velocity in addition to liquid propellants. Solid propellants have long been a mainstay of rocketry, from the sole source of thrust for amateur rockets to auxiliary thrust the Shuttle. However, solid rocket propulsion is ultimately subject to the nastiness of the rocket equation, as is propulsion from liquid ...

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Thrust is another name for force, and force is momentum per time. In other words, to get thrust it is necessary to generate momentum and to keep on doing it. Typically it consists of projecting matter (gas, plasma) away from the vehicle, and the momentum transferred to that matter results in equal and opposite momentum given to the vehicle. The faster the ...

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Since you mentioned liquid fuels explicitly, I feel obligated to bring solid-fuel rockets to your attention. They do not need to be cooled but once ignited, they can headly be stopped until they run out of fuel. Thus, they are primarily used as boosters to aid take-off. E.g. in the space shuttle, the thin white boosters attached to the orange liquid-fuel ...

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Assuming that by escape velocity you mean exhaust velocity, then the velocity comes from the Maxwell-Boltzmann distribution. This gives the velocity distribution of the particles in a gas as a function of temperature. For our purposes we can use the most probably speed, i.e. the peak in the distribution, as a rough estimate and this is given by:  V_e = ...

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First - Excel is a fine tool for doing this kind of simulation at the level you want to do. Just remember that integrating equations of motion involves certain errors - you want to make sure you minimize these errors. Two things you can do: use small time steps, and take the average acceleration / velocity over the time step to compute the new position. So ...

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Without seeing your calculations and a link to the report I can't be sure, but I suspect you are reading the report incorrectly. You say the report lists the takeoff acceleration as $10$ m/sec$^2$, which is over $1$ g. This would be very high for a liquid rocket. Wikipedia lists the takeoff weight as $6,600,000$ lbs and the thrust as $7,648,000$ lbs which ...

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