Lesson: Motion of Planets, Moons, and Satellites Physics • First Year of Secondary School

In this lesson, we will learn how to describe the velocities and accelerations of planets, moons, and man-made satellites that are moving along circular orbits.

Lesson Plan

Students will be able to

state the two main types of orbit: circular and elliptical,
recognize the two main types of orbits from diagrams,
recognize that if two objects (such as a star and a planet) are closer to each other, the force of gravity between them will be greater,
know that for an object in orbit, the force of gravity is always in the direction of that which it’s orbiting,
know that for an object in a circular orbit, the force is always perpendicular to the velocity,
know that for an object in a circular orbit, the acceleration of the object is always in the direction of that which it’s orbiting and always perpendicular to the velocity,
know that for an object in a circular orbit, the smaller its orbital radius, the greater its orbital speed,
know that for an object in an elliptical orbit, when it is closer to that which it’s orbiting, its speed will be greater,
know that the period of a geostationary orbit must be 24 hours,
know that a geostationary satellite must orbit above the equator.