question_answer

A remote sensing satellite of earth revolves in a circular orbit at a height of \[0.25\times {{10}^{6}}\,m\] above the surface of earth. If earth's radius is \[6.38\times {{10}^{6}}\] and \[g=9.8\,m{{s}^{-2}},\] then the orbital speed of the satellite is            [NEET 2015 (Re)]

A) \[7.76\,\,k\,\,m{{s}^{-1}}\]

B) \[8.5\,\,k\,\,m{{s}^{-1}}\]

C) \[9.13\,\,k\,\,m{{s}^{-1}}\]

D) \[6.67\,\,k\,\,m{{s}^{-1}}\]

Correct Answer: A

Solution :

Given, height of a satellite

Earth's radius,

For the satellite revolving around the earth, orbital velocity of the satellite.

Substitutes the value of  and h, we get