page 279
page 280
page 281
assess your understanding
100

What 3 things does the speed of sound?

temperature, stiffness, density of the medium it's traveling through

100

In general, does sound travel faster in solids, liquids, or gases?

solids

100
Define density

how much matter or mass there is in a given amount of space or volume

100
Why does sound usually travel faster in solids than in liquids or gases?

Solids are stiffer than liquids and gases. Sound travels faster in stiffer materials. 

200

Does sound travel faster through hot or cold temperature mediums?

sound travels faster through hot materials.

200

which substance is stiffer - air or water?

water

200

Explain the Channel Tunnel that was talked about on page 281

It was a 50-kilometer-long undersea tunnel with a railway connecting England and France

200
The sounds from a marching band travel _____ when the air temperature is 30*C than when the air temperature is 20*C.

faster

300

Explain how the the particles in a material move based on the temperature.

At lower temperatures, the particles of a material will move slower. At higher temperatures, the particles will move faster. 

300

What is the stiffest substance in the table?

diamond 

300

Why did they use the steel pipes to communicate? 

The workers were too far apart to yell to each other. Steel transmits sound better than air does over long distances.

300

Steel is denser than plastic, yet sound travels faster in steel than in plastic. Develop a hypothesis to explain why. 

Steel is stiffer than plastic. The speed of sound in steel is greater than in plastic because steel's greater stiffness makes up for its greater density.