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## Physics First:Impulse and Momentum Units

This topic presents the physics of impulse and momentum along with lesson plans, activities, reference and content materials. Units are not listed in a prescribed order.

### Teaching about Impulse and Momentum (4)

#### Lesson Plans:

This PTRA manual presents the physics of impulse and momentum and learning materials.  The manual also includes a section on modern physics applications and a set of assessment materials.

Item Type: Instructor's Guide
Level: High School Physics

#### Activities:

This applet features two wagons which can undergo a collision that is either totally elastic or totally inelastic. The simulation is complex enough to allow users to set mass and initial velocity, but simple enough to promote student understanding of physical interactions in colliding systems.

Item Type: Interactive Simulation
Duration: 20-30 minutes

Lots of factors are at play in a simple collision. This resource will help your students build understanding the of following:  1) How to apply the law of momentum conservation, 2) Total energy in a closed system (it's always conserved, but in collisions, kinetic energy is generally transformed into other forms of energy), 3) In special cases (perfectly elastic collisions) the kinetic energy stays the same before and after a collision, 4) In completely inelastic collisions, objects stick together, 5) momentum is a vector.

Item Type: Interactive Simulation
Duration: One class period

#### Content Support For Teachers:

In this 2001 paper presented at the Physics Education Research Conference, authors describe the effects of two teaching approaches in a classroom lab on momentum:  microcomputer-based labs (MBR) and video-based labs (VBR).  Results indicate that students made good use of the information in the lab, and that they spent more time talking about concepts involving conservation of momentum and energy.

Item Type: Reference Material

### Practical Examples for Impulse and Momentum (2)

#### Activities:

This entertaining mini-lesson developed by Exploratorium engages the learner in physical activity to explore the effects of a twisting force (torque) on rotational motion.  By mimicking the motion of a skateboarder, students gain intuitive understanding of the law of conservation of angular momentum.

Item Type: Activity

#### Content Support For Teachers:

This PTRA manual presents the physics of impulse and momentum and learning materials to help students with this topic. Samples from the full print manual are available here. In this book, a section on theory and applications is followed by laboratory, classroom, and computer activities. The manual also includes a section on modern physics applications of the topic. Assessment questions are also provided for use by instructors.

Item Type: Instructor's Guide

### Collisions (2)

#### Activities:

This simulation is a good starting point for learning about collision, as students observe two particles move and collide in one dimension.  The collision is elastic -- caused by a virtual spring.  Students can set starting velocities and spring constant, then view graphs of momentum and kinetic energy alongside the simulation. Editor's Note In the middle school classroom, this item could also serve well as a teacher-led demonstration, with students predicting the motion and graph changes as velocity and spring constant are changed.

Item Type: Interactive Simulation