Lesson: Surface Gravity Physics • 9th Grade

In this lesson, we will learn how to calculate the surface gravity of a planet or moon given its mass and its radius.

Lesson Plan

Students will be able to

understand that the acceleration due to gravity, , experienced by an object in the vicinity of a large object with mass is dependent on and the radial distance between the centers of mass of the two objects, ; so, ,
use to calculate the acceleration due to gravity on the surface of a large body,
understand that the acceleration due to gravity experienced by object in the vicinity of a large object is the same whatever the mass of .

Lesson Video

Lesson Explainer

Sample Question Videos

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Lesson Worksheet

Q1:

Which of the following relations shows how the acceleration due to gravity, , around a massive object varies with the distance away from the center of mass of that object, ?

Q2:

Which of the following relations shows how the acceleration due to gravity, , around a massive object varies with the mass of that object, ?

Q3:

An object orbits a planet at a distance from the planet’s center of mass. The planet has a mass . If the object is moved to an orbit from the planet’s center of mass, by what factor does the local acceleration due to gravity at its orbital radius change?