Electromagnetic waves are related patterns of electric and magnetic force. They travel at the speed of light. They are generated by the back and forth movement, or oscillation, of electric charges. Each wave has a peak and a trough. The distance from one peak to the next is the wavelength of that particular form of electromagnetic energy.

The electromagnetic spectrum consists of bands of different wavelengths.

Demonstrate how each band of different wavelengths may be beneficial. Sight examples of how they may affect us adversely.

Gamma Rays

Positive uses?

Negative effects?

How do we protect ourselves?

X-Rays

Positive uses?

Negative effects?

How do we protect ourselves?

Ultraviolet

Positive uses?

Negative effects?

How do we protect ourselves?

Visible Light (To animal eyes)

Positive uses?

Negative effects?

Do we need to protect ourselves?

What organ do animals have to enable them to interpret visible light?

Develop a table that shows the wavelengths of visible light. What color is associated with each wavelength? Hint: Remember the name ROY G BIV (Red, Orange, Yellow, Green, Blue, Indigo and Violet.) These represent colors visible to the human eye starting at the longer or what is sometime described as the warmer wavelengths.

Infrared

Positive uses?

Negative effects?

How do we protect ourselves?

Microwaves

Positive uses?

Negative effects?

How do we protect ourselves?

Radiowaves

Positive uses?

Negative effects?

How do we protect ourselves?

Hints: Uses of electromagnetic waves

• Doctors use gamma rays to treat cancer and help locate and diagnose internal disorders.
• Ultraviolet rays are used in sun lamps, fluorescent lights and as a disinfectant.
• Infrared rays are found in lamps to treat skin diseases and to bake enamel
• Both ultraviolet and infrared rays transmit voice messages and television signals.
• Microwaves are used to cook food.
• Radio waves appear in radio and TV broadcasting.
• Visible light is the light you can see.