frequency higher frequency = high sound = more waves = shorter wavelength low frequency = low sound...
TRANSCRIPT
Frequency
Higher frequency = high sound = More waves = shorter wavelength
• Low frequency = Low sound =Less waves= longer wavelength
Period of a Wave
• The period is the duration of one cycle in a repeating event.
• Frequency is a measure of the number of occurrences of a repeating event per unit time.
Vibrations• Sound is caused by vibrations
• Sound requires a medium (does not happen in outer space since it is a vacuum.)
• Sound will travel through water at 20 degrees Celsius slower than water at 80 degrees Celsius.
Energy• The amount of energy a wave has
determines it’s amplitude.
Sound
• The unit used to measure sound intensity is the decibel.
• Pitch is how high or low a sound seems to be.
• When a person moves toward a sound, the compressions of the wave are pushed together.
Frequency
• The frequency at which a string vibrates is its natural frequency
• The frequencies of an instrument’s tone that are multiples of the fundamental frequency are overtones.
Instruments• Brass and wind instruments make
sounds by vibrating a column of air.
• Beats are produced by 2 sound with different frequencies
FM
• FM broadcasting is a broadcast technology invented by Edwin Howard Armstrong
• FM carrier wave frequencies vary from 88 Mhz to 108 Mhz
• FM = Frequency Modulation
Radio
• Each radio station broadcasts on one frequency called a carrier wave.
• Information can be added to a radio carrier wave by frequency modulation and amplitude modulation.
Sound
• Violins, harps, and guitars produce sound by vibrating strings.
• A flute player changes the length of a column of air by opening and closing holes which helps make each different sound.
Formulas
Formula Practice• The frequency is 30. What is the
period of the wave.
1/30
The period is 10, what is the frequency of the wave?
1/10