How fast would something need to be traveling to be launched into space?

Question

My understanding is that most satellites are about 100 mile out. How fast would a satellite need to be traveling to be launched those 100 miles from earth? To make it a little easier, lets say the satellite is launched from Denver. Again, no rockets on the satellite, just the velocity needed to overcome the earth’s gravitational pull. Pointing me in the right direction is fine i.e. equations I need, websites, whatever. TIA!

Answer 1

Two things need to happen in order to launch a satellite....the satellite must be lifted up into its orbital altitude and the satellite must be given a "push" (if you will) in the direction of its orbit. Usually, these to things are done simultaneously during launch.

In order to keep the satellite from burning up within Earth's atmosphere and to put it far enough away from Earth's surface to actually make it effective at what it is trying to do (be it a communications satellite or what have you) you need to get the satellite up high.
In order for it to stay in orbit, the satellite must be traveling fast enough in a given direction around the Earth so that it never comes crashing down (it is always falling). This speed is highly dependent upon the type of altitude of the satellite's orbit.

There is no one answer for how fast you would have to launch a satellite to get it into space or orbiting the Earth. Technically, if you could throw something fast enough horizontally here on the surface, it could orbit the Earth, but at this altitude, it would burn up due to air friction.

To calculate the speed needed for a circular orbit at a given radius away from the Earth's center of mass, set the centripetal acceleration equal to the gravitational acceleration experienced by the satellite.
a_c = v^2 / r
g = G * M / r^2
Where v is the satellite's speed, G is the universal gravitational constant, M is the mass of the Earth, and r is the radial distance the satellite is orbiting from the Earth's center of mass.

v^2 / r = G * M / r^2
v^2 = G * M / r
v = sqrt (G * M / r)
G and M are constants, pick a value for r and plug and chuck out the required tangential speed needed to obtain a circular obit.

Answer 2

From a building of certain height, if we throw some object it follows a parabolic path and reaches the ground at a certain distance.

As the speed is increased, the distance of the point of touching the ground (range) also increases.

As the speed is still increased the object encircles the earth and reaches the same spot from which it is thrown. That is the parabolic path now deforms in to a circular orbit.

The speed with which the object should be thrown in order to circle the earth at that height is called orbital velocity.

The orbital velocity is given by the formula v = sqrt (G * M / r)
G and M are constants; r is the distance from the center of earth.

The above formula is valid only if there is no air resistance. But air resistance changes this value very much.

In distances of some hundreds of miles from earth, the air resistance is negligibly small. The orbital velocity at that height is also small.

Thus satellites are taken to that height by rockets and then it is thrown with such a speed so that it circles the earth.

Since they circle the earth, they have not escaped from earth. They are in the earth’s pull and are encircling the earth.

But there is another speed called escape speed. If objects are thrown with such speed they will not encircle earth. And they will escape from the clutch of earth.

For earth the escape speed is 11.2 km/s^ (-1).

Answer 3

First thing, you must examine your understanding of "launched into space". Launched where you would float free of gravity? Putting you up there means you fall right back down, unless you go 2/3 of the way to the moon, then you'd fall to the moon. What you need is orbit. Moving so fast that the curvature of the earth drops out beneath you at the same rate as you fall to earth, giving the appearance of weightlessness because everthing is falling at the same rate (spacecraft, astronauts etc). The speed is somewhere around 17,000 mph. Also note that spacecraft take less energy to achieve orbit when launched at the equator and at the same direction that the earth rotates giving them a speed boost equal to going around the earth 1 time in 24 hours. Moving faster means you move out and the orbital path gets larger. What's the formula? That costs a college education! lol

Answer 4

From the surface of the Earth, escape velocity (ignoring air friction) is about 7 miles per second, or 25,000 miles per hour. Given that initial speed, an object needs no additional force applied to completely escape Earth's gravity.

Answer 5

Low Earth orbit velocity of 7800 m/s = 7.8 km/second

escape velosity of 11 km/second is necessary to leave Earth, not orbit it

Answer 6

the rate variety of bullets can variety from particularly slow velocities, like 2 hundred m/s, to ultrasonic, it quite is extra like 1000 m/s. attack rifle bullets oftentimes have muzzle velocities of 900 m/s. on the different hand, to get into orbit, and merchandise might desire to holiday swifter than approximately 8000m/s, so which you are going to be able to desire to declare that a typical commute travels 8 cases as rapid as a typical bullet

Answer 7

launched at 11.2 km/sec to escape into space beyond the gravitational field

Answer 8

ahhh!!! a terrrorist!!!!! justkiddin....

its inertia that you need, not velocity.