Lesson #30

Lesson #30

EQ: What are the parts of a wave?

​IMPORTANT VOCABULARY

​WAVE

A disturbance in a medium that transfers energy from place to place

​

​MEDIUM

A substance (solid, liquid, or gas) that through which something can travel

1. Mechanical Waves

a. ) Transverse: particles move perpendicular (+) to the direction the wave travels.

Ex: ocean waves

b.) Longitudinal (compressional): particles move parallel (=) to the direction the wave travels.

Ex: sound waves

Multiple Choice

An ocean wave is an example of...

• a transverse mechanical wave

• a longitudinal mechanical wave

Multiple Choice

A wave whose particles move parallel to the direction the wave travels is a...

• transverse mechanical wave

• longitudinal mechanical wave

Transverse waves

The direction of the vibration is perpendicular to the direction of the wave.

Parts of a transverse wave:

Crest: the highest point of a transverse wave.

Trough: the lowest point of a transverse wave.

Parts of a transverse wave:

Wavelength: the distant between two crests or two troughs.

Amplitude: the distance between the middle horizontal line and the highest point or between the middle line and the lowest point.

Wavelength:

Characteristics continued...

Period (T): The time required for one wavelength.

Frequency (f): The number of cycles in a given amount of time (usually 1 second). Measured in Hertz (Hz).

HIGHER FREQUENCY = HIGHER ENERGY

Frequency and Wavelength Relationship

Frequency and wavelength are INVERSELY related....

low frequency = long wavelength

high frequency = short wavelength

Multiple Choice

A wave with a high frequency has...

• a long wavelength

• a short wavelength

Longitudinal waves

The direction of the vibration is parallel to the direction of the wave.

Multiple Choice

Waves with the highest energy have...

• short wavelength, high frequency, and large amplitude

• long wavelength, low frequency, and short amplitude

Parts of a longitudinal wave:

Parts of a longitudinal wave:

Compression: the parts of the wave where the loops are close together.

Parts of a longitudinal wave:

Rarefaction: the parts of the wave where the loops are spread-out.

Parts of a longitudinal wave:

Wavelength: the distance between two compressions.

Multiple Choice

A wave that has the vibration parallel to the direction of the wave is called:

• Longitudinal

• Transverse

Multiple Choice

A wave that has the vibration perpendicular to the direction of the wave is called:

• Longitudinal

• Transverse

Multiple Choice

What does point C represent?

• Crest

• Trough

• Amplitude

• Wavelength

Multiple Select

The wavelength can be measured from ( check all that apply)

• Distance from Crest to Crest

• Distance from Crest to Trough

• Distance from Trough toTrough

• Distance from Crest to midpoint

Multiple Choice

What does point A represent?

• Crest

• Trough

• Amplitude

• Wavelength

Multiple Choice

What does the arrow in the Wave represent?

• Crest

• Trough

• Amplitude

• Wavelength

Multiple Choice

What is A?

• crest

• trough

• rarefaction

• compression

Multiple Choice

What is B?

• crest

• trough

• rarefaction

• compression

Multiple Choice

Which wave has the lowest frequency?

• C

• A

• F

• D

Match

Match the following

• Crest

• Trough

• Amplitude

• Frequency

• Wave Length

The highest part of a transverse wave

The lowest part of a transverse wave

The height of a wave from the center line to the crest

The number of complete cycles of a wave that occur in a unit of time

The distance between two consecutive crests or troughs of a wave

• The highest part of a transverse wave

• The lowest part of a transverse wave

• The height of a wave from the center line to the crest

• The number of complete cycles of a wave that occur in a unit of time

• The distance between two consecutive crests or troughs of a wave

Sound Waves

• Transmitted (passes) through matter (thats why you can hear music from another room)

• Reflected - Waves hitting matter and bouncing off (this is why you hear echoes)

• Absorbed - Transfer of energy of wave with medium it comes into contact with. (no echo)

2.) Electromagnetic (EM) Waves

A waves that does NOT require a medium (matter to travel), has an electric field component and a magnetic field component.

Travels at the speed of light 3.0 x 10⁸ m/s in a vacuum.

Ex: Radio waves, Microwaves, Infrared, Visible Light, Ultraviolet,

X-rays, and Gamma Rays