2003 Virginia SOLs
Motivation for Learning
What is the electromagnetic spectrum? Obtain a large display Electromagnetic Spectrum from a science supplier or put the nice picture shown below in the Student Activity (from Lawrence Berkeley Lab website) up on a screen using a video projector to project your computer screen. Discuss several of the different sources of electromagnetic radiation. The students will probably be surprised to learn that television waves, radio waves, microwaves, visible light, radar waves are actually all exactly the same thing. We can describe them by their wavelength, frequency, or energy, and they are different only by these numerical values. However, their properties are different simply because of these values. A television wave will pass through the walls of our house, whereas visible light will not. Visible light and radio waves pass through Earth's atmosphere, whereas x-rays don't.You may want to look through the various websites given below in the student activity as an inspiration to begin this activity. There are several nice sites, and if you have the ability to project a computer screen on a large room screen, this would be a useful activity.
Electromagnetic radiation (of which visible light is a part) is produced from vibrating electric charges in atoms. The energy travels as a transverse wave that is partly electric and partly magnetic. Other forms of electromagnetic radiation are radio waves, microwaves, and X-rays. The electromagnetic spectrum is the range of electromagnetic waves and ranges from radio waves to gamma rays. The differences among these wave classes rest in their frequencies (and thus their wavelengths). All of them travel at the same speed (3.0 x 108 m/s) in a vacuum.
|Figure 1: from Lawrence Berkeley Lab website|
Students with Special Needs
No special adaptations should be required.