Sound Unit Study Guide

I. What is Sound?

  1. Sound-______
  2. Vibrations go through the air as sound waves, when they reach your ear, they make your eardrums vibrate and thus you hear sound.

II. How Sound Travels

  1. Compression Wave- back and forth motion and its ______is carried along the length of the wave. Draw and label the compression and rarefaction.
  1. Vibrating, particles push into each other
  1. ______when the particles bunch up
  2. ______when the particles spread apart
  1. Wave Diagram
  1. High point= ______
  2. Low point= ______
  3. Middle line= ______
  4. ______is the measurement of energy in the wave
  5. Draw and label a sound wave (amplitude, crest, resting point, trough, wavelength.
  1. ______is the distance from one compression to the next
  2. ______the number of waves produced in a set time
  1. The longer the wavelength, the ______thefrequency.s
  1. The shorter the wavelength, the______the frequency.

III. Sound Mediums

a. Medium- ______(air, water, steel)

b. Density-______

i. The denser the medium the ______sound waves travel through it.

ii. Solids are the ______dense and gases are the ______dense states of matter.

iii. Sound waves ______travel in a vacuum because ______.

c .Temperature

i. The warmer the temperature of a medium, the ______the particles

move.

ii. Sound travels fastest through ______mediums.

IV. Speed of Sound

a. On average sound waves travel at ______in air.

b. On average sound waves travel at ______in steel.

c. The speed of sound changes depending on the ______and

______of the material it is traveling through.

V. How Sound Behaves

a. When sound reflects off of hard objects we call this an ______

b. We hear these ______when we are far away from the reflecting surface

because sound takes time to travel.

c. If there are many reflecting surfaces, the echo will bounce back and forth several

times which we call ______. These sounds are trapped.

d. When sound waves are ______they do not send back reflections.

e. When sound waves cause objects to rattle and therefore make sounds of their own,

we call this ______(airplanes cause windows in your house to

rattle and vibrate creating their own sound) .

f. Echolocation- ______

g. Sonar- ______

VI. Frequency and Pitch

a. Some objects vibrate at a constant rate and produce a steady tone.

b. The highness or lowness of a time is called its ______.

c. The faster something vibrates the ______its pitch.

d. The normal human ear can hear frequencies between ______and ______

vibrations per second.

e. Wavelengths of Sound

i. High-pitched sounds have a ______wavelength.

ii. Low-pitched sounds have a ______wavelength.

VII. Loudness and Intensity

a. Distance- as distance increases, loudness ______

b. Amplitude-

i. the distance that a vibrating object moves as it vibrates

ii. It takes more energy to produce a large amplitude

c. Density-

i. Dense materials have particles that are close together

ii. Sound waves travel faster through denser materials, therefore the waves reach your ear sooner

e. Intensity- amount of energy carried by the sound wave measured in decibels

VIII. Uses and Applications

Instrument (example) / Type / Way it Makes Sound
string
percussion
woodwind
brass