Escape velocity?

Question

Where is the point in space where we need escape velocity to escape from the earth gravitational force. Further we stop suddenly in space after escape from earth gravity then can we observe the earth rotational speed around sun and its sipping.

Answer 1

We need escape velocity at the surface of the earth.  As we get further away, it takes less and less power to move away from the earth, but the gravitational force never goes away completely.  To maintain a "stationary" position in space would require a small amount of force no matter where you are, because there is always gravity, pulling in several different directions.  It would even be hard to tell, in space, when you have stopped moving, because there is no reference point to compare your position to.  On earth, we are used to seeing the road pass by, or feeling the wind in our face, but in space, traveling at 100 mph feels the same as standing still.

We can measure our speed in orbit by the length of the year or our rotational speed by the length of the day without leaving the earth.  It's done by observing the position of the sun and stars.  The observations are accurate enough that we know the length of our year within a fraction of a second.

Answer 2

The escape velocity is the speed we need to reach so that our forward movement is equal to our drop back to earth, about 17,000 miles per hour. At this point we free fall back to earth heading for one spot. But our forward movement makes us constantly overshooting that spot and heading for a new spot. So we stay  in orbit. gravity never disappears. Remember that the sun's gravity reaches out to beyond Pluto, though from pluto the sun looks like a large star, not like we see it.

Answer 3

11km/s