PHYSICS · Multi-part · A Level · Physics · Fields and their consequences · Fields and their consequences
Problem
Two identical artificial satellites, each of mass m, revolve in coplanar circular orbits around Earth. Satellite A moves in an orbit of radius r1=2.0×107m while Satellite B moves in an orbit of radius r2=3.0×107m. Neglect atmospheric drag.
(a) Derive an expression for the orbital speed v of a satellite moving in a circular orbit of radius r around Earth of mass M, assuming gravitational attraction provides the required inward force.
(b) Using the result of part (a), obtain an algebraic expression for the centripetal force on a satellite of mass m in terms of G, M, and r.
(c) Hence find the ratio of the centripetal force on Satellite A to that on Satellite B. Show all algebraic steps before substituting numerical values.