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No. Most of the kinetic energy from a rocket is sideways (8 km/s) so as to let the spacecraft enter orbit. So if you want your orbital airplane, you need an engine that can get up to mach 25 inside of the atmosphere (so you can use relatively efficient airbreathing engines), you need: 1: a high-speed airbreathing engine (a scramjet) 2: a thermal protection ...


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Airplanes always maneuver with respect to the surrounding air. Something which confuses beginner pilots is the following question: imagine you have a wind from north to south, and you point your airplane to the west. Where is the air pressure higher? a. The left side of the plane b. The right side of the plane The answer is: neither. The pressure is the ...


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Just to make things simple, suppose you are standing at the north pole, and you shoot a bullet south at some speed, aiming for a target 1 km away. In the time it takes the bullet to get there, the target has moved east a certain distance, because the target travels in a complete circle around the north pole in 24 hours. From the viewpoint of the shooter, who ...


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Why do airplanes experience negligible Coriolis force while bullets experience the Coriolis force in long range shooting? You are confusing the force with the consequence of the force. Consider a powered parafoil whose total mass is a mere 100 kg (motor+parafoil+pilot) and is moving at a mere 25 km/h and a 50 caliber bullet whose mass is 50 grams and is ...


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I'm assuming that aerodynamic forces are the only allowed sources of lift. Aerodynamically, lift is obtained by redirecting airflow, which is essentially to accelerate air molecules. When you accelerate a mass $dm$ to speed $v$, you gain a momentum $dp$ given by $$dp = v dm$$ Divide both sides by $dt$ to obtain the force: $$F = v \frac{dm}{dt}$$ In ...


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A helicopter can soar using very little power, if its rotor is big and pushes down a large mass of air with very low speed. The limitation is related to strength of a large and low-mass rotor. For example, a helicopter (a quadcopter, actually) using human muscles only was demonstrated recently (https://www.youtube.com/watch?v=syJq10EQkog )


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If using an engine is allowed, then similar to the concept of an actual rocket, we can have Thrust just greater than or equal to weight. Thrust will be equal to rate of mass flow * exhaust velocity f gas from the engine. T= dm/dt * v(exhaust) = mg EDIT :- P = TV = (dm/dt)vv = (m(initial) -(dm/dt)*time)*g


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What affects would traveling at this speed have on the human body? The Earth revolves around the Sun at 18.5 miles per second and humans (as well as other living things) don't seem to notice. In addition, the Sun is travelling around the Milky Way at 143 miles per second. The astronauts and cosmonauts aboard the ISS are travelling at about 4.75 miles ...



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