How g is 0 in satellite?

Question

As in satellite there is zero gravity condition due to absence of normal reaction. But only due to absence of normal reaction we do not feel the weight but it is not like that, that g is 0 in satellite. Is it balanced by some equal and opposite acceleration? Please explain in detail.

Answer 1

Gravity isn't zero in a satellite. Gravity is trying to pull the satellite down to Earth, but at the same time the speed of the satellite is trying to hurl it off into space. The two forces exactly cancel each other and the result is what seems to be zero gravity.

Answer 2

Centripetal accelleration is an outward accelleration caused by rotating about a center point. This accelleration is proportional to the rate of rotation, and the distance from the center of rotation:

a = V^2/R

This corresponds to the force you feel as your going in circles on one of those carnival rides.

When this body is experiencing free fall, it is going at a velocity (and is at a radius) that perfectly balances the acceleration due to gravity:

a = Vff^2/Rff = 9.8m/s

So the force on the satellite due to gravity is balanced (or canceled out) due to the force from Centripetal Accelleration. This the perceived gravity on a satellite in orbit is = 0

Answer 3

Think of standing in a box which is enclosed.

Now if the box is free falling from a high altitude toward the earth, you can easily see that you would be "weightless" inside the box as you would be free falling at the same rate as the box. Much like in an elevator whose cable has broken.
Now imagine that the box has a velocity parallel to the earth's service such that the box moves forward the same distance that it falls - never getting any closer to the surface of the earth - you are still free falling and "weightless."

Answer 4

The acceleration due to gravity (g) is balanced by the acceleration around the orbit (a change in direction). This means that the satalite is essentially constantly falling. This is why you experience zero gravity on a satalite, it is because in your frame of reference you are falling at the same rate as the satalite you are sitting in.

Answer 5

It is balanced by the centrifugal force due to the rotation of the satellite around earth.

In theory you could have a satellite orbit the earth 100 feet above ground, if there was no air (friction) and no obstacles.

Answer 6

For a body on earth we can write the eqn.
mg=GMm/R^2
g=GM/R^2
Where g is the acceleration due to gravity
G is the constant of Gravitation and M is the mass of Earth.
We can see that g starts decreasing as one over squre of distance as we move away fro earth. I space this is as good as zero although some small infinetesimal fraction of g on earth may still be present.