Q. A satellite S is moving in an elliptical orbit around the earth. The mass of the satellite is very small compared to the mass of the earth. Then,
A) the acceleration of S is always directed towards the centre of the earth.
B) the angular momentum of S about the centre of the earth changes in direction, but its magnitude remains constant.
C) the total mechanical energy of S varies periodically with time.
D) the linear momentum of S remains constant in magnitude.
Explanation
[Solution] Gravity is a central force, so the acceleration always points to the earth's centre (and angular momentum and energy are conserved). Answer (1).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.