Main Question or Discussion Point
Why can't we launch satellite by using electromagnet power?
Last edited by a moderator:
The satellite needs to have a large speed to orbit the earth. Most of the accelerating to reach this speed has to be done at a high altitude where the atmosphere is very thin. A railgun that can accelerate something to orbital speed is possible, but the satellite would break up an never reach orbit because of the air resistance.Why can't we launch satellite by using electromagnet power?
One assumes that you are not counting the Earth's gravity as a "further acceleration". Then yes, a 11 km/sec velocity at the surface in any direction yields a trajectory that will escape to infinity, barring any other acceleration. Typically, that other acceleration will be present either by smacking head-on into the Earth's surface (if you aim downward) or air resistance (if you aim upward).Intuitively, if one ( or the vehicle ) could instantaneously achieve 11km s-1 at the surface , would it
of necessity escape the pull of the earth's mass (gravity) if it did not undergo ANY further acceleration?
See https://www.physicsforums.com/threads/could-a-1g-acceleration-vehicle-escape-earths-gravity-well.954278/Similarly, if one had a hypothetical rocket that had an unlimited supply -internallyproduced- of thrust ,
then could that rocket continue into space / orbit without actually achieving the so-called ESCAPE VELOCITY?
Not that this changes the question much, but I thought I would mention that orbital velocity is less than escape velocity.As an addendum , do you always have to reach the standard escape velocity ?