Editor selections by Topic and Unit

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## Physics First:Periodic and Simple Harmonic Motion Units

Simple Harmonic Motion (SHM). The motion that occurs when an object is accelerated towards a midpoint or equilibruim position. The size of the acceleration is dependent upon the distance of the object from the mid-point. Examples of this type of motion are sea waves, pendulums and springs. Units are not listed in a prescribed order.

### Simple Harmonic Motion (6)

#### Lesson Plans:

This lesson integrates a computer model to help kids visualize how energy is conserved in a simple pendulum (a child swinging on a swing). Students can drag the swing to different heights, then activate the motion. As the swing moves in periodic motion, energy bar graphs are shown in real-time.....letting students see the changing levels of kinetic and potential energy. Highly recommended by editors. Includes full lesson plan and printable student guide. Easily adaptable for high school.

Item Type: Simulation-Based Lesson
Duration: One Class Period

This multimedia module was created by the American Association for the Advancement of Science and aligned to AAAS Benchmarks. It opens with Galileo's pendulum experiments, continues with interactive simulations of pendulum motion, and concludes with a hands-on lab.

Item Type: Instructional Module
Duration: Two days

#### Activities:

The amount of time it takes a pendulum to swing back and forth stays the same when you change its weight. But what if you took the pendulum to another planet? This animation lets students interactively explore pendulum length, the force of gravity, and rotation of the planet to see how they affect the motion of the pendulum.

Item Type: Interactive Animation

This simple, yet creative Java simulation offers a way for students to explore the connection between uniform circular motion and SHM.  It will help build understanding of the basic equation for objects undergoing simple harmonic motion. The editors suggest using this resource with the interactive homework problem "Block and Spring" directly below.

Item Type: Interactive Simulation

This Java model explores the motion of a block attached horizontally to an ideal spring. You can change the mass of the block, spring constant, and initial position. The model will display energy bar graphs and graphs of position, speed, and acceleration as a function of time. Try teaming this simulation with the interactive homework problem (directly below) to promote deep understanding of the sinusoidal nature of SHM.

Item Type: Interactive Simulation
Duration: 30 minutes

#### Student Tutorials:

This robust, yet easy-to-use interactive model can be adapted for learners ranging from middle school through AP physics. You can change the string length, mass, and initial angle. Change the gravitational constant to see how the pendulum moves on different planets. View real-time bar graphs to see how energy is converted from kinetic-to-potential and back as the pendulum swings. Advanced learners can view graphs of angular acceleration/velocity.

Item Type: Interactive Simulation

### Conservation of Energy and Forces on a Spring (3)

#### Activities:

In this realistic virtual mass-and-spring laboratory, students explore spring motion by hanging weights of different masses on springs. Students can adjust the spring stiffness and damping. (Damping is a force, often friction, that reduces amplitude.) Real-time charts show changing kinetic, potential, and thermal energy levels as the springs oscillate. Can be adapted for a variety of levels and capabilities.

Item Type: Interactive Simulation