Explain the concept of a force law as an empirical relation between the force exerted on an object and properties of the object.
Be able to use Newton’s Third law when analyzing problems involving more than one object.
Be able to construct a force diagram to represent the forces exerted on the system by other objects that interact with the system.
Explain how empirical force laws are used in Newton’s 2^nd law.
Explain the relationship between the description of motion and Newton’s 2^nd law.
Be able to explain the meaning Newton’s 1^st law: physical laws (such as force laws) are the same in all inertial reference frames.

Course Notes

Notes: The Concept of Force (PDF - 5.3MB)

Video Excerpts

Watch the following excerpts from the Physics I lecture videos:

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» Clip 1: Newton's First, Second, and Third Laws (49 min)
» Transcript (PDF)

From Lecture 6 of 8.01 Classical Mechanics, Fall 1999

» Clip 2: Weight and Weightlessness (50 min)
» Transcript (PDF)

From Lecture 7 of 8.01 Classical Mechanics, Fall 1999

» Clip 3: Frictional Forces (48 min)
» Transcript (PDF)

From Lecture 8 of 8.01 Classical Mechanics, Fall 1999

Download the complete lectures from this course:

» iTunes U
» Internet Archive

Guided Activities

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

Slides: Concept of Force (PDF - 1.8MB)

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.