H R Y T RD M R D E RD N X T P TE O N

Hint: The first word starts with T.

H R Y T RD M R D E RD N X T P TE O N L

What are the parts of a wave?

Transverse wave The crest is the highest point on a transverse wave. The trough is the lowest point on a transverse wave.

The rest position of the wave is called the node or nodal line.

The wavelength is the distance from one point on the wave to the next corresponding adjacent point.

Compressional Longitudinal wave

On a compressional wave the area squeezed together is called the compression. The areas spread out are called the rarefaction.

The wavelength is the distance from the center of one compression to the center of the next compression.

What is the amplitude of a wave?

The amplitude of a wave is directly related to the energy of a wave.

The amplitude of a compressional wave is determined by the closeness of the compressional waves. The closer the compressional waves and the farther the rarefaction lines.

The amplitude of a transverse wave is determined by the height of the crest or depth of the trough

The Nature of Waves

• What is a wave?

• A wave is a repeating disturbance or movement that transfers energy through matter or space

Waves transfer energy not matter. The water waves below are carrying energy but are not moving. Waves can only exist as they have energy to carry.

What are mechanical waves?

Mechanical waves are waves which require a medium. A medium is a form of matter through which the wave travels (such as water, air, glass, etc.) Waves such as light, x-rays, and other forms of radiation do not require a medium.

What are the two kinds of mechanical waves?

Longitudinal Waves (Compression Waves)

In a longitudinal wave the matter in the wave moves back and forth parallel to the direction of the wave

Example of a transverse wave:

Electromagnetic Waves

Electromagnetic Waves

• Wave which is capable of transmitting its energy through a vacuum (i.e., empty space)

• Produced by the vibration of electrons within atoms on the Sun's surface

• Travel through space until they reach Earth These waves subsequently travel through the vacuum of outer space, subsequently reaching Earth

What are Electromagnetic Waves?

• Electromagnetic waves are waves which do not require matter to transfer energy.

• Electromagnetic waves need no medium like sound and water waves.

• Electromagnetic wave can travel in a vacuum

• Electromagnetic waves all travel 300,000,000 meters per second in a vacuum

Electromagnetic spectrum

The electromagnetic spectrum is the entire range of electromagnetic waves arranged according to their frequencies or wavelengths.

Electromagnetic waves all have different properties. But they all travel the same speed – what we call “The speed of light”

Forms of electromagnetic radiation

•Visible light 400 to 700 nm – This is the only form of electromagnetic wave visible to the human eye.

•Ultraviolet – these cause our skin to darken (tan) and can even damage our skin. The ozone layer protects us from most UV radiation from the sun.

•X-rays – these EM waves pass through much matter. It doesn’t pass through dense bone, so it is useful in determining whether a bone is broken or not.

The Electromagnetic Spectrum More than meets the eye!

Examples from Space!

Wavelength

• The distance from one wave crest to the next

• Radio waves have longest wavelength and Gamma rays have shortest!

Mechanical Waves

• Are not capable of transmitting its energy through a vacuum (space)

• Require a medium in order to transport their energy from one location to another

Mechanical Waves

• Waves traveling through a solid medium can be either transverse waves or longitudinal waves

• Waves traveling through a fluid (such as a liquid or a gas) are always longitudinal waves

What are mechanical waves?

Mechanical waves are waves which require a medium. A medium is a form of matter through which the wave travels (such as water, air, glass, etc.) Waves such as light, x-rays, and other forms of radiation do not require a medium.

What are the two kinds of mechanical waves?

Transverse Waves

In a transverse wave the matter in the wave moves up and down at a right angle to the direction of the wave