# Conics and Reflection

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This page first made public: Mar 17, 2010

This material was originally developed through Merlot

as part of its collaboration with the SERC Pedagogic Service.

#### Summary

In this activity, students will investigate the reflective properties of the parabola, the ellipse, and the hyperbola. They will look at applications that relate to both the collection of incoming signals and signals that are emitted from a source and reflected by the conic. They will first make discoveries utilizing interactive animations and then will complete a worksheet where they will write down these observations.

## Learning Goals

2. Figure out the use of the reflective properties in the context of lighting devices, receptors, and other technologies.

3. Understand that the conics sections are more than just a set of equations or geometric axioms.

## Context for Use

## Description and Teaching Materials

1. http://www.ies-math.com/math/java/conics/focus/focus.html

2. http://www.ies-math.com/math/java/conics/focus_ellipse/focus_ellipse.html

3. http://www.ies-math.com/math/java/conics/focus_hyper/focus_hyper.html

The best situation would be for the students to work in a computer lab environment where they explore the properties. Otherwise, the instructor can present the applets using an Internet enabled computer with a projector. During the exploration period the instructor can facilitate discussion that will lead the students towards more thoughtful answers to the worksheet questions.

After exploring with the applets, the students are given the worksheet. Students can either work on their own or in pairs or groups.

## Teaching Notes and Tips

## Assessment

## References and Resources

This site contains 9 JAVA applets that allow the student to interactively discover the reflective and other geometric properties of conic sections.