An artificial satellite is moving in a circular orbit around the earth with a speed of equal to half the magnitude of escape velocity from earth.
(i). Determine the height of the satellite above the earth's surface
(ii). If the satellite is stopped suddenly in its orbit and allowed to fall freely on the earth. Find the speed with it hits and surface of earth. Given `M="mass of earth & R "="Radius of earth"

Options

A. 2 R
B. `(R)/(2)`
C. R
D. `(R)/(4)`

Answer

C

Explanation

It is given that `sqrt((GM)/(r))(1)/(2)sqrt(2gR)=sqrt((gR)/(2))=sqrt((GM)/(2R))`
`:. r=2RrArrh=r-R=2R-R=R`