In this introduction to light energy, students learn about reflection and refraction as they learn that light travels in wave form. Through hands-on activities, they see how prisms, magnifying glasses and polarized lenses work. They also gain an understanding of the colors of the rainbow as the visible spectrum, each color corresponding to a different wavelength.
Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards.
All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standard Network (ASN), a project of JES & Co. (www.jesandco.org).
In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc.
Click on the standard groupings to explore this hierarchy as it applies to this document.
- Colorado: Science
- International Technology and Engineering Educators Association: Technology
- C. Energy comes in different forms. (Grades 3 - 5)  ...show
- Next Generation Science Standards: Science
- Make observations to provide evidence that energy can be transferred from place to place by sound, light, heat, and electric currents. (Grade 4)  ...show
- Understand that light is a form of energy and that it can be characterized as a wave.
- Comprehend that different colors of the spectrum represent light waves vibrating at different frequencies.
- Describe reflection and refraction of light waves.
- Understand how engineers use light waves.
Lesson Background and Concepts for Teachers
|Electromagnetic spectrum:||The entire range of wavelengths or frequencies of electromagnetic radiation extending from gamma rays to the longest radio waves and including visible light. In order of decreasing frequency: cosmic-ray photons, gamma rays, x-rays, ultraviolet radiation, visible light, infrared radiation, microwaves and radio waves.|
|Lens:||A curved piece of glass that refracts light waves.|
|Light energy:||Visible light energy, such as from a light bulb, fireflies, computer screens or stars, is one form of electromagnetic energy. Others forms include infrared, ultraviolet, radio and x-ray. Your eyes are detectors of visible light energy.|
|Light speed:||The speed at which light travels in a vacuum. Defined as exactly 299,792,458 meters per second. (A measure of speed.)|
|Light year:||The distance that light travels in a vacuum in one year. Defined as 9.46 trillion kilometers or 5.88 trillion miles. (A measure of distance, not time.)|
|Photon:||A tiny particle or packet of energy. The quantum of electromagnetic energy, generally regarded as a discrete particle having zero mass, no electric charge and an indefinitely long lifetime.|
|Polarization:||The phenomenon in which waves of light or other radiation are restricted in direction of vibration.|
|Prism:||A solid figure whose bases or ends have the same size and shape and are parallel to one another, and each of whose sides is a parallelogram. A transparent body of this form, often of glass and usually with triangular ends, used for separating white light passed through it into a spectrum or for reflecting beams of light.|
|Reflect:||To give back or show an image of an object, for example, in a mirror. Light reflects or "bounces" off the surface of an object.|
|Refract:||The bending of light as it crosses the between the surface of two transparent materials.|
|Refraction:||The ability of light to bend when it crosses a transparent medium.|
|Wave:||(Physics) A disturbance traveling through a medium by which energy is transferred from one particle of the medium to another without causing any permanent displacement of the medium itself.|
|Wavelength:||The length between peaks or troughs of a wave. This distance determines the color of a beam of light.|
- Stations of Light - Student groups rotate through four stations to examine light energy behavior: refraction, magnification, prisms and polarization.
- What are some types of light energy we have discussed? (Answers: Visible, x-ray, radio, ultraviolet, infrared.)
- Which is brighter, a laser or the sun? (Answer: A laser, because it has more concentrated light energy than the sun.)
- What other type of energy does the sun give off? (Answer: Besides light, the sun also gives off heat.)
- Can you hear someone yell in the room next door? (Remind students that sound must travel through matter [air, walls, etc.].) Does light function in the same way? (Point out that we receive light from the sun through the vacuum of space. Light can move through air, water, glass and other transparent material.)
- Can you see a black cat in the dark? Why or why not? (Explain that when we see an object, our eyes are detecting the light reflecting off of the object. So, our eyes cannot detect anything in the absence of light. Black objects reflect no light; white objects reflect all light.)
Lesson Summary Assessment
Lesson Extension Activities
Dictionary.com. Lexico Publishing Group, LLC. Accessed September 22, 2005. (Source of some vocabulary definitions, with some adaptation.) http://www.dictionary.com/
Electromagnetic Spectrum. Updated 1997-2005. NASA's Imagine the Universe, Goddard Space Flight Center. Accessed September 22, 2005. (Good basic description and graphics) http://imagine.gsfc.nasa.gov/docs/science/know_l1/emspectrum.html
Graham, I., Taylor, B, Farndon, J. and Oxlade, C. Science Encyclopedia. 1999, p. 78-90.
Irving, Bruce. Optics for Kids: Science and Engineering. Optical Research Associates, Pasadena, CA. Accessed September 28, 2005. (Excellent resource with graphics) http://www.opticalres.com/kidoptx.html
Sharon D. Perez-Suarez, Jeff Lyng, Malinda Schaefer Zarske, Denise Carlson
© 2005 by Regents of the University of Colorado
Integrated Teaching and Learning Program, College of Engineering, University of Colorado Boulder
Last modified: August 28, 2015