The Moon revolves round the Earth in an almost circular path of radius and completes…
PHYSICS · Multi-part · A Level · Physics · Fields and their consequences · Fields and their consequences
Problem
The Moon revolves round the Earth in an almost circular path of radius 3.84×105km and completes one revolution in 27.3days. Treat the Moon’s orbit as exactly circular for all calculations.
(i) Obtain an expression for the mass of the Earth in terms of the orbital radius r of the Moon and its time period T of revolution.
(ii) Using the above data, calculate the numerical value of the Earth’s mass in SI units.
(iii) The accepted value of the Earth’s mass is 5.97×1024kg. Find the percentage error in your result obtained in part (ii).