Consider On Earth Satellite So Positioned That It Appears Stationary To An Observer On Earth And Serves The Purpose Of A Fixed Relay Station For Intercontinental Transmission Of TV and Other Communications. What Would Be The Height At Which The Satellite Should Be Positioned And What Would Be The Direction Of Its Motion? Given That The Radius Of The Earth Is 6400 Km And Acceleration Due To Gravity On The Surface Of The Earth Is 9.8m/s2.

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Consider on earth satellite so positioned that it appears stationary to an observer on earth and serves the purpose of a fixed relay station for intercontinental transmission of TV and other communications. What would be the height at which the satellite should be positioned and what would be the direction of its motion? Given that the radius of the earth is 6400 km and acceleration due to gravity on the surface of the earth is 9.8m/s2.


Correct option is


For a satellite to remain above a given point on the earth’s surface, it must rotate with the same angular velocity as the point on earth’s surface. Therefore the satellite must rotate in the equatorial plane from west to east with a time period of 24 hours.

Now as for a satellite   


So the height of the satellite above the surface of earth,


[The speed of a geostationary satellite 



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