Module C  Chapter 1  Sound Waves

Sound is a form of energy that is produces by vibrations traveling in waves.  As the sound travels through matter, it can vary in pitch and volume.

Many sounds help people and animals survive.

Vocabulary;

energy                 vibrate                 volume                 pitch          

matter            gas             liquid          solid            echo           

Chapter 1/Module C

Lesson 1.1  Making Sound

Sounds keep us safe by warning us of danger.

·       Smoke alarm

·       Fire truck

·       Ambulance

·       Tornado siren

Sounds help animals  to stay alive.

·       Warn of danger

·       Find food

How is Sound Made

          Sound is a kind of energy.

1.     Sounds are created when matter vibrates.

Vibrate – means to quickly move back and forth.

2.     Sound energy moves out from the object in all directions, producing sound waves.

Electricity is another kind of energy.

1.     Flows into the telephone when a call comes into your house.

2.     Electrical energy makes the bell ring.

3.     Electrical energy stops flowing when and the ringing stops.

Different Volume

Volume is the loudness or softness of a sound.

The volume of a sound that an object makes when it is hit depends on how hard the object is hit.

·        Large bell/Large clapper on a bell creates more energy so it is louder.

·        Smaller bell/Smaller clapper on bell creates less energy so it is softer.

Loud sounds can help to keep you safe…

Loud sounds can be harmful to your ears.

Different Pitch

Pitch of a sound is how high or low the sound is.

1.    An object vibrating slowly creates a low pitch and sound waves are farther apart. (Large bell)

2.    An object vibrating quickly creates a high pitch and sound waves are close together. (Small bell)

Checkpoint…

1.  Can you tell how a sound is made?

2.  What kinds of objects can make sound?

3.     How can you cause an object to make a loud sound?

4.      Why does a small bell make a higher pitched sound than a large bell makes?

Lesson 1.2  How  Sound Travels

Sound Moving Through Matter

·        Sound waves move out in all directions

·        Sound travels through matter.            

·        Matter may be a solid, liquid, or gas (Three States of Matter).

·        Sound waves travel through matter by causing the particles in matter to vibrate and bump into other particles of matter.

·        The energy of sound moves from one particle of matter to another as they bump.

·        Sound waves travel fastest where the particles of matter are the closest together.

Solid

1.    wood

2.    The particles of matter in wood are close together.

3.    Sound travels fastest through a solid/wood because the particles are so close together.

Liquid

1.    Water

2.    The particles of matter in water are farther apart.

3.    Sound travels slower through liquids/water because the particles are farther apart.

Gas

1.    Air

2.    The particles of matter in air are the farthest apart.

3.    Sound travels slowly through air/gas because the particles are so far apart.

Echoes

·        Echo is a sound that bounces back from an object.

·        Might hear an echo if you are surrounded by hills or cliffs.

·        Dolphins and bats use echoes to find their food.

1.     Dolphins and bats make sounds as they move.

2.     Then the sound hits an object it bounces back to that dolphin or bat.

3.     Then the dolphin or bat knows where their food (fish/dolphin, insects/bats) is.

4.     Bats also use sounds to help them fly at night because they don’t see well.