The Horizontal Circle Simulation is an adjustable-size file that displays nicely on smart phones, on tablets such as the iPad, on Chromebooks, and on laptops and desktops. The size of the Interactive can be scaled to fit the device that it is displayed on. The compatibility with smart phones, iPads, other tablets, and Chromebooks make it a perfect tool for use in a 1:1 classroom.


Teaching Ideas and Suggestions:

This Interactive is intended for use near the early to middle stages of a learning cycle on circular motion. The Interactive simulates three examples of an object moving in a horizontal circle:
  • The motion of a ball suspended from the end of a string and whirled in a circle
  • The motion of a ball (or car) horizontal, banked turn (without the need for friction)
  • The motion of an airplane flying in a horizontal circle
Users can easily toggle between the three instances of moving in a horizontal circle and make comparisons between relationships, the direction of forces and accelerations, and the cause-effect relationship between variables. The simulation offers the option of viewing it from the side, from above, or from any angle in between. Force vectors (and their components) can be displayed. Acceleration vectors can be displayed as well. Several sliders allow the user to change the values for parameters associated with the motion and view the impact of such changes immediately. Finally, a numerical output display shows values of the most common motion quantities.

The provided exercise that accompanies this Interactive guides students towards an understanding of the forces and their components and the effect that changes in mass, speed and radius have upon other variables. Teachers are encouraged to use the exercise with their classes.

Our Horizontal Circle Simulation is now available with a Concept Checker. Do the simulation. Then follow it up with the Concept Checker.


Related Resources

There are numerous resources at The Physics Classroom website that serve as very complementary supports for the Horizontal Circle Simulation. These include:
  • Minds On Physics Internet Modules:
    The Minds On Physics Internet Modules include a collection of interactive questioning modules that help learners assess their understanding of physics concepts and solidify those understandings by answering questions that require higher-order thinking. Assignments CG1, CG2, CG3, CG4 and CG5 of the Circular Motion and Gravitation module provide great complements to this Interactive. They are best used in the middle to later stages of the learning cycle. Visit the Minds On Physics Internet Modules.

  • Curriculum/Practice: Several Concept Development worksheets at the Curriculum Corner will be very useful in assisting students in cultivating their understanding, most notably ...

    Speed and Velocity
    Acceleration and Circular Motion
    Circular Motion and Inertia
    The Centripetal Force Requirement
    Mathematics of Circular Motion

    Visit the Curriculum Corner.

  • Labwork: 
    Simulations should always support (never supplant) hands-on learning. The Laboratory section of The Physics Classroom website includes several hands-on ideas that complement this Interactive. Two notable lab ideas include ...

    Making the Turn Lab
    Loop-the-Loop Lab

    Visit The Laboratory.
  • Science Reasoning Activities:
    Science classrooms should be filled with reasoning activities. There is one related activity in the Circular Motion section of the Science Reasoning Center that will challenge students to employ close reading, data analysis, and logical reasoning. The activity is named ...

    Roller Coaster Loops

    Visit the Science Reasoning Center.

Additional resources and ideas for incorporating Horizontal Circle Simulation into an instructional unit on circular motion can be found at the Teacher Toolkits section of The Physics Classroom website.  Visit Teacher Toolkits.


We owe a special thanks to Physics teacher Martin Kirby for donating the Horizontal Circle Simulation to our Interactives collection. If you like this sim, you can tap on the Donate button and buy him a cup of coffee (or a pot of coffee); he'd appreciate it. Martin has contributed many other simulations to our Interactives collection. You can view them all by visiting our page listing all Martin Kirby Simulations. Or visit Martin's website ( to learn more.

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