the Physics Education Technology Project
This interactive simulation provides four components for exploring balanced and unbalanced forces. In the introductory activity, users choose from among 5 objects of different masses, set the surface with or without friction, then "push" the object along a straight line. The simulation displays force vectors and free body diagrams to match the motion. Record your "push" and replay to see the sum of forces. The second activity focuses on the role of friction when objects are pushed on a wood surface. Set your own gravitational constant and watch the effects on static and kinetic friction. The third activity lets users display simultaneous graphs of applied force, acceleration, velocity, and position. The final activity, "Robot Moving Company", is a game where users apply a force to deliver objects of different mass from one point to another.
Editor's Note: This simulation may be adapted to a broad range of student capabilities. See Related Materials for links to guided explorations for middle school and high school, created by PhET teacher-fellows.
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, Newton's 3rd Law, acceleration graph, force interactions, force pairs, forces, free body diagram, net force, position graph, velocity graph
Metadata instance created
September 27, 2011
by Caroline Hall
March 17, 2014
by Caroline Hall
Last Update when Cataloged:
August 15, 2011
AAAS Benchmark Alignments (2008 Version)
4. The Physical Setting
4E. Energy Transformations
6-8: 4E/M2. Energy can be transferred from one system to another (or from a system to its environment) in different ways: 1) thermally, when a warmer object is in contact with a cooler one; 2) mechanically, when two objects push or pull on each other over a distance; 3) electrically, when an electrical source such as a battery or generator is connected in a complete circuit to an electrical device; or 4) by electromagnetic waves.
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.
9-12: 4F/H1. The change in motion (direction or speed) of an object is proportional to the applied force and inversely proportional to the mass.
9-12: 4F/H4. Whenever one thing exerts a force on another, an equal amount of force is exerted back on it.
11. Common Themes
6-8: 11B/M4. Simulations are often useful in modeling events and processes.
Next Generation Science Standards
Motion and Stability: Forces and Interactions (HS-PS2)
Students who demonstrate understanding can: (9-12)
Analyze data to support the claim that Newton's second law of motion describes the mathematical relationship among the net force on a macroscopic object, its mass, and its acceleration. (HS-PS2-1)
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)
All positions of objects and the directions of forces and motions must be described in an arbitrarily chosen reference frame and arbitrarily chosen units of size. In order to share information with other people, these choices must also be shared. (6-8)
Newton's second law accurately predicts changes in the motion of macroscopic objects. (9-12)
Crosscutting Concepts (K-12)
Cause and Effect (K-12)
Cause and effect relationships may be used to predict phenomena in natural or designed systems. (6-8)
Science and Engineering Practices (K-12)
Analyzing and Interpreting Data (K-12)
Analyzing data in 6–8 builds on K–5 and progresses to extending quantitative analysis to investigations, distinguishing between correlation and causation, and basic statistical techniques of data and error analysis. (6-8)
Analyze and interpret data to provide evidence for phenomena. (6-8)
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)
Modeling in 9–12 builds on K–8 and progresses to using, synthesizing, and developing models to predict and show relationships among variables between systems and their components in the natural and designed worlds. (9-12)
Develop and use a model based on evidence to illustrate the relationships between systems or between components of a system. (9-12)
Using Mathematics and Computational Thinking (5-12)
Mathematical and computational thinking at the 9–12 level builds on K–8 and progresses to using algebraic thinking and analysis, a range of linear and nonlinear functions including trigonometric functions, exponentials and logarithms, and computational tools for statistical analysis to analyze, represent, and model data. Simple computational simulations are created and used based on mathematical models of basic assumptions. (9-12)
Use mathematical representations of phenomena to describe explanations. (9-12)
Create or revise a simulation of a phenomenon, designed device, process, or system. (9-12)
This resource is part of a Physics Front Topical Unit.
Topic: Dynamics: Forces and Motion Unit Title: Newton's Second Law & Net Force
This wonderfully updated version of the PhET Forces simulation lets students explore force interactions, motion graphs, and friction at a broad range of levels. Choose from 5 objects of different masses, select a wood or ice surface, then "push" the object on a straight path. You can display force vectors, free body diagrams, and graphs of position, acceleration, and velocity vs. time. Record your "push" and play it back to see the sum of forces. For more advanced students: set gravitation to mimic the Moon or Jupiter and watch the effects on static and kinetic friction!
%0 Electronic Source %D August 15, 2011 %T PhET Simulation: Forces and Motion %I Physics Education Technology Project %V 2014 %N 17 April 2014 %8 August 15, 2011 %9 application/java %U http://phet.colorado.edu/en/simulation/forces-and-motion
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