Be able to determine the conditions under which a rigid body is in static equilibrium.
Be able to calculate the magnitude and direction of the torque about any point due to any force using vector decomposition and the cross product.
Be able to calculate the magnitude of the torque about any point due to any force using the lever-arm for the perpendicular distance or the perpendicular component of the force.
Analyze a rigid-body statics situation using a systematic methodology. Be able to:
- choose a co-ordinate system based on the specific situation in the problem;
- determine the net force and net torque about a suitable point on a rigid body;
- apply the conditions of static equilibrium to determine conditions that the forces must satisfy.

Course Notes

Notes: Static Equilibrium (PDF - 2.7MB)^#

Video Excerpts

Watch the following excerpts from the Physics I lecture videos:

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» Clip 1: Static Equilibrium, Stability, Rope Walker (48 min)
» Transcript (PDF)

From Lecture 25 of 8.01 Classical Mechanics, Fall 1999

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Guided Activities

Read through the class slides carefully. They explain all of the concepts from the module.

Slides: Static Equilibrium (PDF - 1.2MB)^#

Self-Assessment

Do the Concept Questions first to make sure you understand the main concepts from this module. Then, when you are ready, try the Challenge Problems. If you are struggling with the Challenge Problems, watch the Homework Help Session videos, which will give you tips on how to tackle problems of this type.