DOI: 10.36347/SJPMS.2019.v06i11.005

Pages: 195-200

Combining Kepler’s second law with the Universal law of gravitation in case of an elliptic orbit of a satellite around the Earth, Kepler’s third law is derived. Given the elliptic orbit of a satellite it is proved that its motion is governed by the inverse-square law of gravitation and its orbital elements subject to the initial conditions are determined. The time period of the elliptical orbit is determined applying Inverse –square law without involving Kepler’s law. However, this is done by evaluating a definite integral with a technique other than that available in the relevant textbooks. While closing, two examples demonstrating Inverse –square law of attraction and repulsion, ie, Coulomb’s law have been worked out for the sake of pedagogy.