Question

Two satellites A and B move round the earth in the same orbit. The mass of B is twice the mass of A.
(a) Speeds of A and B are equal.
(b) The potential energy of earth+A is same as that of earth+B.
(c) The kinetic energy of A and B are equal.
(d) The total energy of earth+A is same as that of earth+B.

Answer 1

Explanation:

• a) Speeds of A and B are equal.  As velocity is independent of mass, speed of the two satellites A and B remain same and they move around the earth with same velocity in the same orbit.  
• But, the potential energy and kinetic energy depend on mass.  
• Therefore, the total energy also depends on mass.  Here, the mass of A and B satellites varies.  
• Hence the energies dependent on mass also varies for the two satellites.  Also, the speed is dependent on radius of orbit.