This page will collect the contributions from the teachers who have used this unit, in total or in part, in the classroom. Initially it just contains a few "teaching suggestions" which we could call "theoretical", although they are based on our teaching experience. "Gravitational field" is aimed at students in the second year of post-compulsory secondary education. The subject should have already been studied in the forth year of secondary education with a less formal approach. The objectives of this unit in the last year of post-compulsory education are:

• To understand the process that lead to the establishment of the law of universal gravitation and its relation with Kepler's empirical laws.

• To explain the importance of the law of gravitation in the study of the movement of astronomical objects in the solar system, artificial satellites and tides.

• To learn the concepts of field intensity and gravitational potential energy.

• To understand how phenomena like Earth's rotation may change our perception of gravity.

• To be able to carry out predictions of the values of field intensity, orbital data of satellites or energy in gravitational phenomena in simple cases.

We welcome all types of contribution such as the time taken to work the unit, problems, suggestions for improvement, criticism, aims achieved, etc, at: