wave calculations. there are different physical parts of a wave. amplitude, crest, trough, wave...
TRANSCRIPT
Wave Calculations
• There are different physical parts of a wave.• Amplitude, Crest, Trough, Wave Length
Wave Speed
• But what if I want to know how long it takes for a wave to travel or how many waves go by in a second? Do I have to stand there and count waves?
• Answer: NOPE! We can use math.
Period
• Period is how long it takes for one wave length to pass by or one full rotation of a particle.
• Period is represented by the symbol “T”.
• It is measured in seconds.
Frequency
• Frequency is how many waves can pass by in a given time frame. (How rapidly the vibrations occur).
• The symbol for Frequency is:
• It is measured in hertz (Hz). 1 Hz is 1 wave per second.
Frequency and Period Equation
• The more waves per second the faster each wave is traveling. That means Frequency and the Period are related.
• Frequency = 1/Period• Written as symbols:
Wave Speed
• You already know the formula for speed:
• So lets apply that to waves:– Wave speed = wave length / Period– In symbols:
Wave Speed
• But there is another way….
• Since the frequency is 1/T I can multiply the wave length times the frequency.
• Wave speed = • In symbols:
The Medium Matters
• The speed of a wave depends upon the medium it is traveling through.
• State of the medium, the type of medium and the temperature of the medium all matter.
The Type of Wave Matters
• The type of wave also determines the speed.
• Electromagnetic waves do not need a medium.
• All electromagnetic waves travel through a vacuum at c = 2.99792458 x 108 m/s.
Put them in a medium and they get bounced around.
Doppler Effect
• How a wave sounds (pitch) depends upon the frequency.
• Meaning the more waves pass by in a second the higher the pitch.
• This can be created by the Doppler effect.