Kepler's Third Law Tutorial



Planetary Motion Tutorial
Kepler's Third Law:
     Kepler's Third Law states that The squares of the orbital periods of planets are directly proportional to the cubes of the semi-major axis of the orbits.

Planetary Motion Formula:
Satellite Orbit Period:
Satellite Mean Orbital Radius:
Planet Mass:
where,
G = Universal Gravitational Constant = 6.6726 x 10-11N-m2/kg2
r = Satellite Mean Orbital Radius
M = Planet Mass

Kepler's Third Law Examples:
Case 1: The period of the Moon is approximately 27.2 days (2.35x106 s). Determine the radius of the Moon's orbit.
 Mass of the earth = 5.98x1024 kg, T = 2.35x106 s, G = 6.6726 x 10-11N-m2/kg2.
  Step 1: Substitute the values in the below Satellite Mean Orbital Radius formula:
           
This example will guide you to calculate the Satellite Mean Orbital Radius manually.

Case 2: Determine Jupiter's mass, which orbits Jupiter at an orbital radius of 4.218 x 108 at every 151200 seconds.
 r = 4.218 x 108 m, T = 151200 s, G = 6.6726 x 10-11N-m2/kg2.
  Step 1: Substitute the values in the below Mass formula:
           
This example will guide you to calculate the Mass of the object manually.



This tutorial will help you dynamically to find the Planetary Motion of Kepler's Third Law problems.