Activities

1. What is a vibration?
   
   
2. Define pitch.
   
   
3. Define reflection.

4. Explain how vibrations are related to the pitch of a sound.
   
   
5. Summarize how the sound of a door slamming reaches your ear.

6. There is no matter in outer space.  If you were in outer space and wanted to sing a song, would you hear yourself?  Explain why or why not.

Answer Key/Rubric

1. Vibration is when particles of matter move back and forth quickly.
2. Pitch is how high or low a sound is.
3. Reflection is when sound bounces off of a surface.
4. Acceptable responses may include, but are not limited to:

• A high frequency wave makes more vibrations per second.
• A low frequency wave makes fewer vibrations per second.
• The more vibrations per second, the higher the pitch.
• The less vibrations per second, the lower the pitch.

5. Acceptable responses may include, but are not limited to:

• The slamming door causes air molecules to move.
• When the molecules that were moved by the door bump into other molecules around them, the energy of the sound is carried.
• If there is enough energy, the air molecule will continue to bump into each other until the energy reaches your ear.

6. Acceptable responses may include, but are not limited to:

• Sound needs molecules to carry the energy in the wave.
• Since there is no matter in outer space, there are no molecules to carry the energy.
• You would not be able to hear any sound in outer space because there are no molecules to carry the energy of a sound wave.