the Physics Education Technology Project
This middle school lesson plan, with a step-by-step student guide, was developed for use with the PhET simulation Forces and Motion. It provides explicit directions for using the simulation in the middle school setting, with tips on how to present concepts of force interactions in a way that is developmentally appropriate for young adolescents. After completing this activity, students will be better prepared to identify when an object is being acted upon by unbalanced forces and predict the change in motion when a force is applied to an object.
This resource is part of PhET, the Physics Education Technology Project, a collection of simulation-based learning objects developed for learners of physics, chemistry, math, earth science, and biology.
Please note that this resource requires
Java Applet Plug-in.
Newton's 2nd Law, force interactions, force pairs, forces, free body diagram, net force
Metadata instance created
September 27, 2011
by Caroline Hall
August 14, 2016
by Lyle Barbato
Last Update when Cataloged:
August 15, 2011
AAAS Benchmark Alignments (2008 Version)
4. The Physical Setting
3-5: 4F/E1a. Changes in speed or direction of motion are caused by forces.
3-5: 4F/E1bc. The greater the force is, the greater the change in motion will be. The more massive an object is, the less effect a given force will have.
6-8: 4F/M3a. An unbalanced force acting on an object changes its speed or direction of motion, or both.
11. Common Themes
6-8: 11B/M4. Simulations are often useful in modeling events and processes.
Next Generation Science Standards
Disciplinary Core Ideas (K-12)
Forces and Motion (PS2.A)
The motion of an object is determined by the sum of the forces acting on it; if the total force on the object is not zero, its motion will change. The greater the mass of the object, the greater the force needed to achieve the same change in motion. For any given object, a larger force causes a larger change in motion. (6-8)
Relationship Between Energy and Forces (PS3.C)
When two objects interact, each one exerts a force on the other that can cause energy to be transferred to or from the object. (6-8)
Crosscutting Concepts (K-12)
Cause and Effect (K-12)
Cause and effect relationships may be used to predict phenomena in natural systems. (6-8)
NGSS Science and Engineering Practices (K-12)
Developing and Using Models (K-12)
Modeling in 6–8 builds on K–5 and progresses to developing, using and revising models to describe, test, and predict more abstract phenomena and design systems. (6-8)
Develop and use a model to describe phenomena. (6-8)
This resource is part of a Physics Front Topical Unit.
Topic: Dynamics: Forces and Motion Unit Title: Newton's Second Law & Net Force
This lesson plan for Grades 6-8, with printable student guide, is a great supplement to the PhET simulation Forces and Motion. The winner of a PhET "Gold Star", it was developed by an experienced teacher to provide explicit guidance for students as they use the simulation to investigate force interactions. We like it because it provides just the right amount of help to navigate the simulation, while also allowing students to construct their own meaning from the model.
%0 Electronic Source %D August 15, 2011 %T PhET Teacher Activities: Balanced and Unbalanced Forces %I Physics Education Technology Project %V 2017 %N 24 February 2017 %8 August 15, 2011 %9 application/java %U https://phet.colorado.edu/en/contributions/view/3423
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