Attributes of Physics of Sound Flashcards
Explain the difference between a transverse wave and a longitudinal wave.
Transverse wave occurs when individual molecules move up and down at right angles. Example: wave motion of water when a pebble is thrown into it.
Longitudinal wave has molecules that move in the same direction that the wave is traveling. Example: sound wave.
Explain the differences between compression and rarefaction.
Compression is the occurrence of high pressure when the molecules of a wave approach and collide with each other.
Rarefaction is the opposite of compression, occurring in times of low pressure when molecules are distant from other molecules. In a wave, compression looks like wavelengths with their peaks close together. Rarefaction looks like wavelengths that are spread out, with peaks further apart.
How does fundamental frequency change for adults, children, males, and females?
The fundamental frequency, or natural pitch, of a child is a higher frequency than an adult. A child’s vocal tract is shorter in length than an adult’s/ A child’s vocal folds are also physically smaller than adult vocal folds. A child’s vocal folds produce rapid and small vibrations, which are perceived as high pitch and quiet. Once puberty begins, the vocal folds elongate, allowing more room for vibration. This results in a slower and larger wave that is perceived as low pitch and loud.
Does a human’s voice produce a pure periodic tone, a pure aperiodic tone, a complex periodic tone, or a complex a periodic tone?
Complex aperiodic tone
What is the formula to find the frequency when given the period (T)?
F=1/T
What is the formula to fine the period when given the frequency?
T= 1/F
What is the formula to find a wavelength?
Wavelength = C/F C= 331 m/s (speed of sound)
What are the general properties of sound waves that affect how we hear the sound or not?
1) Frequency, perceived as pitch
2) Intensity (amplitude), perceived as loudness
3) Phase, how a soundwave relates to other sound waves in terms of constructive or deconstructive interference.
What is a pure tone and what is a complex tone?
Pure town contains one frequency and a complex tone contains more than one frequency
What does periodic mean and what does aperiodic mean?
A periodic wave repeats in an even pattern and an aperiodic wave is random and does not repeat.
What is reverberation?
When there are multiple places in which the sound waves are reflected, allowing the listener to hear the soundwave even after the original source of the sound has stopped.
What is absorption?
Dampening of a wave due to a medium absorbing the wave and lessening the intensity.
What is reflection?
When soundwaves bounce back in the opposite direction from transmission.
What is refraction?
When a wave changes direction because of a local difference in temperature in the air. Example: you are camping on a lake and you see other people on the opposite side but you can’t hear them. At night, you can see them and hear their conversation. The speed of the wave depends on the elastic and inertia properties in which the medium travels. When the wave experience different medium and the wave speed is different, the wave will change directions hence why they could be heard at night.
What is diffraction?
How a soundwave moves when it gets to the edge of an object, gap, or opening. The disturbance in the waves once through the gap spreads through the space in a spherical fashion.
