 1) Determine the wave speed of a wave that has a period of 3 minutes and a wavelength of 0.05 m.  2) How are electromagnetic and mechanical waves different?  3) Determine the period of a wave that has a wavelength of 5.51m and a wave speed of m/s.  4) As wavelength of a wave increases, what happens to the wave’s frequency?  5) Does energy of a wave increase or decrease when the wave’s frequency increases?

 Is a disturbance or vibration that travels through a medium as a longitudinal wave.  Sound waves travels in all directions away from the sound source. › Move or vibrate the medium back and forth along the path the wave travels.

 Starts with a vibration, then the vibrations cause the particles in the medium to vibrate, and they bounce back and forth as the wave travels through them.

 Amplitude- Is related to how spread out the particles are in the compressions and rarefactions (Longitudinal Wave)  Determines the loudness of sound.

 Loudness- Perception of the energy of a sound or describes what you hear  Measured in decibels (dB)  Depends on 2 factors- › 1. Amount of energy it takes to make the sound › 2. Distance from the sound source  The larger the amplitude, more than the energy and louder that sound is  Intensity- Amount of energy a sound wave carries per second through an area. › Greater the intensity, louder the sound

 Pitch- How high or low the sound seems to a person. › Depends on the frequency of the sound wave  Pitch: › Higher the frequency, higher the pitch  Measured in Hertz (Hz)  People usually hear between 20 Hz and 20,000 Hz

 Change in frequency of a wave as its source moves in relation to an observer.  How this happens- › Frequency of a moving object is higher than if the object was not moving  Frequency changes because the motion of the source adds to the motion of the waves › Example- Throwing a tennis ball at a wall while moving

 Sound waves travel in all directions away from their source. › Ex: People in a gym hearing a radio playing  The medium does not travel with the sound waves. › They only vibrate back and forth.

 Travels at different speeds in different mediums  Depends on 3 things-  1. Elasticity- Ability of a material to bounce back after being disturbed › How well the particles of the medium bounce back after they are disturbed › The more elastic the medium, the faster sound travels  2. Density- How much mass or matter there is in a given amount of space or volume › In the same state of matter, sound travels faster in less dense materials.  3. Temperature- The greater the temperature, the faster the speed of sound

 The speed of sound- › Solid-Normally faster than Liquids and Solids › Liquids- Faster than gases › Gases-Slowest  Subsonic- Objects that travel slower than the speed of sound › Helicopter  Supersonic- Objects that travel faster than the speed of sound › Jet breaking the speed of sound

 Occurs when sound waves combine in patterns that are pleasing.  Sound Quality- Result of several pitches blending together through interference  Resonance- Occurs when 1 object causes another object to vibrate at a natural frequency.  Noise- Has no pleasing patterns.

 Acoustics- Study of how sounds interact with each other and the environment › Used to design concert halls  Reverberations- Multiple echoes that are produced when reflected sound and direct sound build up and blend together.

 What is the function of your ears?  Explain the function of the inner ear?  What do sound waves make your eardrum do?  Discuss what the cochlea is?  Describe how vibrations move through the cochlea.  What part of your body tells you that you have heard sound?