wave notes
DESCRIPTION
Wave Notes. Waves General and Electromagnetic. Waves carry energy & information The information carried could be: Sound Color Pictures Radio waves – tv Microwave – cell phones WAVES DO NOT CARRY THE MEDIUM!!! (Ex: water). Transverse Waves. Energy moves left to right - PowerPoint PPT PresentationTRANSCRIPT
Wave NotesWaves
General and Electromagnetic
• Waves carry energy & information
• The information carried could be:–Sound–Color–Pictures
• Radio waves – tv• Microwave – cell
phones• WAVES DO NOT
CARRY THE MEDIUM!!! (Ex: water)
Transverse Waves• Energy moves left to
right• Wave moves up & down
–Ex: water waves–A Rope that is moved up
and down–Light
• Wave and energy move perpendicular to each other.
Longitudinal Waves• Wave and
energy are in same direction–Ex: Slinky–The
compression will move along the slinky forward and then back.
–Sound
Also called Compressional Waves
–Crests: high point of the wave
–Troughs: low point of the wave
Parts Of A Transverse Wave
Wavelength ( ):–The length of one complete cycle of a wave.
–From crest to crest or trough to trough.
AmplitudeHow big or little the wave is. Tells you how much energy the wave has.The bigger the wave, the more energy it has.
Parts of a Longitudinal Wave• Compression-The condensed portion
• Rarefaction-The separated part of the wave.
• Wavelength-distance from compression to compression
Frequency• How many waves pass in 1 sec.• A wave carries its frequency to
every area that it reaches• Measured in hertz (Hz)
Speed of a Wave• How fast the
wave can transfer energy.
• v = f x • v = speed
(velocity) Units=m/s
• f = frequency Units=Hz
• = wavelength Units=m
• TRANSVERSE WAVES!!!!• All travel at the same speed• The difference is in the frequency and the wavelength.
If one goes up, the other goes down.
Parts of the EM Spectrum
• Radio Waves-Longest wavelength, lowest energy, lowest frequency.
• Used for TV’s, Radios and Cell Phones
Microwaves• A form of radio waves-some books place
them separately and some put them in with radio.
• They are the highest frequency (most energy) of the radio waves.
Infrared (IR)• Heat• Used to find people
in the woods.• Infrared film
detects how hot something is.
• Use to detect cancer
• Beneath red
Visible Light• ROY G. BIV-colors
of visible light.• Sunlight emits UV
along with other rays.
• Gives us Vitamin D• Too much harmful.• Most filtered by
ozone.• Red is longest
ultraviolet• Main source is sunlight• Helps your body produce vitamin D• Overexposure = burns and skin cancer• Sunscreen helps to block• Beyond violet
X-rays and Gamma Rays
• X-rays-See bones.• High Energy• Use lead to block!• Gamma rays-
highest energy• Use to treat cancer• Generated by
radioactive atoms
Wave Interactions• Interaction -Wave run into
other object or another wave• Interaction can increase or
decrease wave energy• Interaction can change the
properties of the wave• Interaction can change the
direction
Reflection• A wave bouncing off
of a surface– Mirror– Wave hitting a wall
• Incident wave – moving to surface
• Reflected wave – moving away from surface
Refraction• Bending of wave as it changes
speed• Speed changes from on medium
to another–Air to water–Water to oil
Diffraction• Bending of a wave when it comes
into contact with the edge of another object
• Light bending around a door
Interference• The effect of 2 or more waves
interacting• Can be constructive or destructive
Constructive Interference
• Wave crest come together at the same location
• Waves join together to make a larger wave
Destructive Interference• The crest of one wave
meets the trough of another wave
• Crest and trough subtract from each other to make a smaller wave
• Sometimes the interference cancels both waves
Doppler Effect• Sound• Change in frequency
and pitch of a sound that is caused by either the movement of the source or the listener
• Ambulance• Race car