General Physics for Competitive Exams

Concept of geo-stationary orbit was  suggested by "Arthu C Clarke". Geo-stationary orbit is at a height of 36,000 KM from earth.   India's first communication satellite is "Apple".                                                                                                                                                                                       PSLV - Polar Satellite Launch Vehicle.                              PSLV can launch satellites in orbits at height 900       Cryogenic engines are used in GSLV.    Satellite application center is in Ahmedabad.    Liquid propulsion system centre is in Tiruvanantapuram.    Periscope is used in submarines. It is in Z shape.    Solid Carbon-Di-Oxide is called as dry ice.  Minimum escape velocity for a rocket to be launched into space is 11.2 km/sec.   India's first launched geostationary communication satellite was "APPLE".  First lady to set on space voyage is Swetlana Savitskaya.  Communication satellites are placed  in parking orbits. Time period of revolution of a satellite around a planet is independent of mass of satellite.  Time period of a surface satellite of earth is 84.6 min or 1.4 hours.  Apparent weight of a body in a satellite is zero.  Worlds first woman astronomer is Valentina teriskova.  The orbit in which a geostationary satellite moves is called parking orbit.  Relative velocity of parking satellite with respective to earth is zero.  Time period of revolution of geo-stationary satellite is 24 hours.  Orbital linear velocity is about 3 Km-sec-1 .  It should revolve from west to east in equatorial plane.  For Geo-stationary satellite the time period is equal to rotation of earth about its axis.