Physics GEO-STATIONARY SATELLITE

Please Wait... While Loading Full Video

GEO-STATIONARY SATELLITE

Geo-Stationary Satelite :

If there is a satellite rotating in the direction of earth's rotation, i.e., from west to east, then for an observer on the earth the angular velocity of the satellite will be `(w_s-w_E)`

However, if `w_s -w_E= 0`, satellite will appear stationary relative to the earth. Such a satellite is called 'Geo-stationary satellite' and is used for communication purposes.

We know that, `T^2 = (4 pi^2)/(GM)r^3`

For geostationary satellite, `T = 24` hours. Putting this value of Tin the above equation,
we get `rapprox 42000` `km` or, ` h approx 36000` `km`.

where `h` Is the height of the satellite from the surface of the earth.

Weightlessness in a Satellite :

The radial acceleration of the satellite is given by `a_r = F_r/m = (GMm)/(r^2 xx m) = (GM)/r^2`

For an astronaut inside the satellite, we have

`(GMm_a)/r^2-N-m_a a_r=0`

where m , is mass of astronaut a , is radial acceleration of
satellite and N is normal reaction on the astronaut

`(GMm_a)/r^2-N-(GMm_a)/r^2=0=> N=0`

Hence, the astronaut feels weightlessness.