JEE Mains ..Some point related to Gravitation

• Speed of a satellite circulating around the earth is independent of it's mass.
• Speed of satellite rotating in larger orbits is lesser.
• If the kinetic energy of a satellite is doubled , it will escape to infinity.
• Polar satellites are used for remote sensing of earth but geostationary satellites are used for the purpose of communication.
• Orbits of geostationary satellite and polar satellites are mutually perpendicular.
• Dimensionally, gravitational potential is same as latent heat.
• If variation of g is accounted for then gravitational potential energy of a particle of mass m raised to height h from earth surface, will gain potential energy by amount. m g h / ( Re +h).
• A satellite rotating around the earth will sweep area at rate L /2M where L is it's angular momentum and M is it's mass.
• Polar satellites have height around 500 to 1000 km above the earth.Their time period is around 2 hrs.
• Taking potential energy zero at infinity, for a satellite rotating around the earth, total energy is negative, potential energy is negative and magnitude of potential energy is twice of that of the magnitude of total energy. Magnitude of the kinetic energy is same as magnitude of the total energy.For example if the kinetic energy is 1000 joules, then total energy will be -1000 joules and potential energy is -2000 joules.
• Any energy of rotating satellite is inversely proportional to the radius of the orbit.
• If the radius of two satellites differ by one percent, then their time periods will differ by 1.5 percent.