ELECTROMAGNETIC (EM) SPECTRUM March 17-18, 2014

How long is each wavelength?

Radiowaves  Longest wavelength  Low frequencies  AM- modify amplitude  Long distance communication  Prone to signal interference (that fuzzy buzzing sound)  FM- modify frequency  Short distance communication  Less likely to be interfered with  Used in:  TVs,  Radios  Walkie Talkies  Negatives:  Very sensitive to electronic interference  Can’t go very far distances (won’t help us talk to people on the moon)

Microwaves  Still long wavelength  Low frequencies  Long, long distance communication (like to outer space and back)  Used in:  Microwaves  Radar (speed guns)  Satellites  Cell phones  Negatives: Can they cause cancer?

Infrared (IN-FRA- RED)  Comes from objects (every object has heat)  Main source: THE SUN!, lightbulbs  Is heat being absorbed and then released by objects  Need special equipment to see  Used:  Law enforcement (find the bad guys)  Warm yourself  Negatives:  Sunburn  Heat stroke (if absorb to much heat)

Visible Light aka ROY G. BIV  Middle of the spectrum (smallest part though)  Lets us see  When all are together= white light  Negatives:  Damage eyes  Can come from light sources like:  The sun  Lamps

Ultraviolet aka UV  From sun, lamps, basically any light source  Used for:  Sterilization  Vitamin D production= calcium absorption (healthy bones)  Happy moods  That lovely tan from the beach  Negatives:  Sunburn  Cancer if too much exposure  Eye damage

X-rays  Second shortest wavelength  High frequency  Pass through almost anything (excluding some elements like Lead (Pb))  Used for:  Security  Medical observation  Negatives:  Too much = mutation of cells  Kill healthy cells

Gamma Rays  Shortest wavelength  Highest frequencies  Can pass through anything  Used for:  Killing germs/bacteria in food  Nuclear medicine (cancer treatments, thyroid treatments, etc…)  Negatives:  Kill/damage cells  Can be left over from nuclear explosions  Mutations! Ahhhh!