The Electromagnetic Spectrum 9/9/18

OSCILLATION Movement back and forth at a regular speed In the case of electromagnetic waves the oscillation move all at the same speed.

ELECTROMAGNETIC WAVES All electromagnetic waves are the same The only difference between all is their frequency of oscillation. This means the energy that each electromagnetic wave is capable of depositing in matter. REMEMBER all waves have the same speed. Speed of light.

The Many Uses of Electromagnetic Wave Phenomenon in Our Daily Lives.

Radio Waves Longest wavelength Primarily used in radio and television communication Also used in radar systems, and satellites

NOTES on antennas and Radio Waves

Microwaves Most familiar with the use of a microwave for cooking. This Photo by Unknown Author is licensed under CC BY

Microwaves Microwaves are also used in: 1. aircraft navigation 2. Radar 3. scientific research

Infrared (IR) waves Wavelength longer than visible light Readily absorbed and emitted by most materials.

Infrared (IR) waves When absorbed objects get hotter by increasing the kinetic energy of atoms and molecules

Infrared (IR) waves IR application include in meteorology, night-vision devices, communication, and astronomy.

Detectable by the human eye Ranges from Violet to Red Visible light Detectable by the human eye Ranges from Violet to Red

Human eyes are not equally sensitive to all wavelengths Visible Light Human eyes are not equally sensitive to all wavelengths

NOTES on visible spectrum

NOTES on visible spectrum

NOTES selective absorption and reflection

Ultraviolet (UV) Light Sun is a significant source of UV light The atmosphere absorbs most of the UV light

Ultraviolet (UV) Light Large amounts of UV light is harmful to humans Use in the sterilization of medical instruments

Sterilization The process of making something free from bacteria or other living microorganisms

X-rays Most familiar application of X-rays is in medicine for the examination of the bones. X-rays are energetic enough to be harmful to living tissue This Photo by Unknown Author is licensed under CC BY-ND

Gamma Rays Highly penetrating waves that are emitted by radioactive nuclei Extremely hazardous to living tissue and cause irreversible damage if absorbed.

Gamma Rays Yet, this energy can be used to destroy harmful cells such as cancerous tumors.