Question

Motion of artificial satellite around the earth is powered by :

• A. Liquid fuel
• B. Solar energy
• C. Atomic energy
• D. None of these

Answer 1

Answer: (D)

None of these

Answer is D.
The orbit of an artificial earth satellite is an ellipse whose focus is at the center of the earth (in a particular case, a circle) and which maintains an unchanged position in space. Movement along such an orbit is called undisturbed motion and proceeds on the assumption that the earth attracts, according to Newtons law, like a sphere with spherical density distribution and that the satellite is affected only by the earths gravitational attraction.
Such factors as atmospheric drag, compression of the earth, solar radiation pressure, and the attraction of the moon and sun are the reasons for deviations from undisturbed motion. Because of atmospheric drag, satellites in orbits at altitudes of several hundred kilometers gradually descend and, entering the dense layers of the atmosphere at an altitude of 120130 km and lower, disintegrate and burn up; thus, they exist for a limited period.
Hence, the motion of artificial satellite around the earth is NOT powered by any of the options given.