Sound Unit Review QA and SS

Sounds that we hear are caused by...

• vibrations

• volume

• decibels

• materials

Volume describes when sounds are loud or quiet. A louder sound is caused by...

• faster vibrations

• smaller vibrations

• bigger vibrations

• slower vibrations

Smaller vibrations produce a....

• higher pitch

• louder sound

• lower pitch

• softer sound

Sounds can be high-pitched or low-pitched. Which animals make high-pitched noises:

• mice

• lions

• bats

• elephants

High-pitched noises are made by vibrations that are...

• faster and closer together.

• slower and far apart.

• bigger and slower.

• smaller and faster.

Low-pitched sound is made by vibrations that are...

• faster and close together.

• bigger and faster.

• slower and far apart.

• slower and smaller.

What is a control variable?

• The variable that stays the same.

• The variable that is changed.

• The variable that is measured and recorded.

What is a dependent variable?

• The variable that stays the same.

• The variable that is changed.

• The variable that is measured and recorded.

What is an independent variable?

• The variable that stays the same.

• The variable that is changed.

• The variable that is measured and recorded.

Some friends conduct an investigation. They take a variety of different materials such as a book, a bottle of water, and a balloon. They choose a small bell as a source of sound. They play the sound of a bell ringing on one side of each of the materials and use a decibel reader to measure the sound volume of the sound waves. They made a table of the results.

In this investigation what is the dependent variable?

• The source of the sound used.

• The materials used to block the sound waves.

• The volume of the sound.