Physical Science Ch. 13

We know sound is a wave because(5 reasons)

1. Has a frequency 2. Has a wavelength 3. Has a speed 4. Can be reflected, refracted, and absorbed 5. Interference and defraction

Name 2 factors that affect the speed of sound in a material.

1. Pressure 2. Temperature

While the range of human hearing is 20hz to 20,000hz, humans hear best in the range from:

100-2,000hz

The frequency of the "c" above middle C is...

528hz

Pressure

A measure of the force felt by the walls of the container holding the gas.

Sonogram

A special kind of graph that shows how loud "sound" is at different frequencies.

We get our sense of hearing from the ___, a tiny fluid filled organ in the inner ear.

Cochlea

What describes 2 or more sounds that are pleasant to hear together?

Consonance

What is the unit for loudness of sound?

Decibels

Why are there "dead spots" sometimes in a concert hall?

Destructive interference

What describes 2 or more sounds that are unpleasant to hear together?

Dissonance

Fewer molecules make the pressure go...

Down

The shorter the wavelength the___ the frequency

Higher

There are 2 main types of waves. Of which type is a sound wave?

Longitudinal

Would you hear an explosion in space?

No, because there is no sound in space

We hear the different frequencies of sound as having different...

Pitch

The harmonic motion is an oscillation in___ and the wave is a___ wave.

Pressure; longitudinal

Rhythm

Rapid alternations between loudness and silence.

What describes motion faster than the speed of sound?

Supersonic

2 musical instruments may play at the same note and yet they do not sound the same. What gives each instrument it's characteristic sound?

The combination of frequencies

Reverberation

The multiple echo you hear when sound waves reflect from hard surfaces.

Acoustics

The science and technology of sound

Harmony

The study of how sounds work together to create effects desired by the composer and based on the frequency relationships of the musical scale

What is used to make internal images of the human body?

Ultrasound

The more molecules per unit volume make the pressure go___.

Up

What is an equal mixture of all frequencies of sound?

White noise