The entire range of the various kinds of radiation.

Wavelength increases…………. Frequency decreases………..

The range of electromagnetic waves that can be detected by the human eye. Wavelengths are in the middle range of the spectrum. The longer the wavelength, the lower the energy of the wave.

The human eye reacts to different frequencies of light so that different colors are seen. Higher frequencies (shorter wavelengths) are perceived as colors toward the blue-violet range and have higher energy. Lower frequencies (longer wavelengths) are perceived as colors toward the orange-red range and have lower energy.

The range of electromagnetic waves lower than red in visible light. (Wavelength longer, energy lower) Hotter objects emit more infrared radiation than cooler objects. Heat energy is transmitted by infrared radiation. When objects absorb infrared radiation, they become warmer.

Infrared Examples: Heat Seeking missiles Heat vision goggles TV Remote controls Wireless mouse

The range of electromagnetic waves higher than violet in visible light. (Wavelength shorter, energy higher) UV Radiation comes from the Sun and causes: The production of Vitamin D. (Benefit) Tanning, sunburn, and/ or skin cancer. (Hazardous) UV Radiation can also: Sterilize surgical equipment Detect counterfeit money ID drugs Also, a bee’s vision is in ultraviolet.

Longest wavelengths: >30cm Lowest frequencies: <10 9 Hz AM radio 910 = 910,000 Hz Radio Telescopes

Wavelength and frequency between infrared and radio. Uses: Microwave ovens Global Positioning Systems Cell Phones

Wavelength shorter and frequency higher than UV. Uses: Medical imaging (X-rays and CT scans) Airport security

Shortest Wavelengths: < meters Highest Frequencies: > Hz Uses: Irradiation of foods to kill bacteria Cleaning of surgical instruments Radiation therapy (cancer treatment) Nuclear Bombs

Eye Anatomy: Detects the visible light range of the electromagnetic spectrum Pupil

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