Bell Work

• List 5 different kinds of waves you have seen in your lifetime.

What are Waves?

Objectives:• How do matter and

energy interact when waves are generated?

• What are the three main types of waves?

What is a WAVE?• A disturbance that transfers energy from

place to place.

• Waves carry energy!

• After the wave has moved, the disturbance is gone. Everything is calm again.

How does a wave travel?• A wave must have something to

travel through. MATTER!

• The material through which a wave travels through is called a medium.

What are some examples of mediums that waves can

travel through?

Mechanical Waves

• Waves that require a medium through which to travel through are called mechanical waves.

• Waves do not carry the medium as they move through it.

• Waves just carry energy.

• The duck does not move sideways toward to shore.

• The duck moves up and down and the WAVE moves toward to shore.

Electromagnetic Waves

• Not all waves require a medium in order to travel.

• Light from the sun can travel through empty space. Empty space is not a medium

What CAUSES waves?• Waves are generated when a source

of energy forces the matter in a medium to vibrate.

• Vibration is a repeated back-and-forth or up-and-down motion.

• Motion is the source of the wave.

The transfer of energy:

• A moving object has energy.

• The moving object can transfer energy to a nearby medium, creating a wave.

transfer

Wave Motion

Energy

Mechanical waves

Electromagnetic waves

A medium to pass through

include

requiredon’t require

Waves

include

Classification• Waves are classified according to how they travel

through a medium.

• Three types of waves:

1. Transverse waves

2. Longitudinal waves

3. Surface waves

Transverse Wave

• Waves that move the medium at right angels to the direction in which the waves are traveling.

• Across

• Highest part of the wave is called the crest.

• The lowest part of the wave is called a trough.

Transverse Wave

Can you think of any transverse waves?

Longitudinal Wave

• Moves the particles of the medium parallel to the direction that the waves are traveling.

• Coils of a spring• Compressions – parts where the coils are close

together• Rarefactions – parts where the coils are spread out

Longitudinal Wave

Can you think of any longitudinal waves?

Surface Wave

• Combinations of transverse and longitudinal waves.

• The waves occur at the surface between two media, such as water and air.

• Up and down and back and forth

Objectives Review:• How do matter and energy interact

when waves are generated?

• What are the three main types of waves?

Assignment: