Visible light is just a tiny slice of radiation that makes up the electromagnetic spectrum. In order from lowest energy to highest energy, and longest wavelength to shortest wavelength, the radiation types are: radio, microwave, infrared, visible light, ultraviolet, X-rays, and gamma rays.
All radiation is not harmful. Light is a form of radiation. All parts of the electromagnetic spectrum are considered radiation, but only X-rays and gamma rays are made up of harmful, ionizing radiation. Ionizing radiation is dangerous because it can penetrate body tissues and cause cell damage. Ultraviolet light from the Sun causes sunburn, which is a common form of harmful radiation. Radiation with wavelengths equal to or longer than visible light (radio, infrared, and visible light) is considered harmless.
The primary colors of light are red, green, and blue, while the primary colors of pigments are red, yellow, and blue. When combined, the primary colors of pigments produce a black pigment, while the primary colors of light produce white light.
In astronomy, the color of an object does not always signify its temperature. An object's color can mean many different things, including its distance from Earth, its temperature, and its chemical makeup.
Filters don't change the color of light, but they do allow only certain colors of light to pass through, and block the others.
"Myths vs. realities: Light and color" contains common misconceptions about the electromagnetic spectrum, light and color. The misconception is presented as the “myth” and an explanation of the true concept is the “reality.” Teachers should be aware of the misconceptions students harbor because they impede students' ability to see the “big picture” in the various sciences; hamper students' ability to apply science principles meaningfully to everyday life; and diminish students' ability to appreciate the links among science concepts and generalizations.
This resource aids teachers in identifying and remedying student misconceptions about the electromagnetic spectrum, light and color. The best way to learn how students think is to ask them. Below are two strategies that can be employed to identify your students' misconceptions concerning the electromagnetic spectrum, light and color. The first is an individual writing activity that allows students to think independently. The other is a group activity that allows students to share their ideas verbally.
An individual writing activity. To prepare for a study of the electromagnetic spectrum, light and color, explain that you are interested in finding out what your students already know about this topic before you start. Ask students to write down what they know about the electromagnetic spectrum, light and color and why they know it. For example, they may say the primary colors of light are red, blue, and yellow because these are the primary colors of pigments. Collect their papers and compile a list of misconceptions the students display in their writing.
The next day, start your unit by explaining that it is common for people both children and adults to have misconceptions about their world. Explain that you have a list of misconceptions that you would like to discuss with the class. You can read the misconceptions that appear on Myths vs. realities as well as the ones compiled from the students' papers. Ask the students to comment on the misconceptions and discuss the reality of the situation. If your students have misconceptions about the electromagnetic spectrum, light and color that we haven't included on our list, you can send them to us through the Contact us section of this web site, and we'll add them to our list. You may want to make special mention of any new misconceptions the students revealed, and let them know you'll submit them to us for addition to our list.
A group activity. Begin your study of the electromagnetic spectrum, light and color by explaining to students that sometimes the ideas they have about this topic may not be entirely true, and that you are going to try to identify these ideas. Explain that some of these ideas are very hard to remove, and that even their parents may have some of these misconceptions Tell the students that you will read a statement (either a myth or a reality) and they must decide whether it is true or false. Ask them to explain their decision in writing.
Once students have written their responses, discuss their thoughts and the accuracy of the statement. Be sure to establish some ground rules concerning student responses to the thoughts of their peers. Remind them that almost anyone can hold these misconceptions, but they need to be identified and removed before true learning can begin. Ask students if they have any other misconceptions that are not covered in the activity, so you can submit them to us for addition to our list through the Contact us section of this web site. It might help students feel more invested in the activity.
Amazing Space resources by topic: Electromagnetic Spectrum/Light & Color