# data[].attributes.body
I can understand that waves transfer energy from the place where they form (source) to another place

# data[].attributes.body
A repeating movement or disturbance that transfers energy through matter or space

# data[].attributes.body
T he basic properties (parts) of a wave include frequency, amplitude, wavelength, and speed.

# data[].attributes.attachment_link.description
Wavelength is typically a measurement from the crest to crest of a transverse wave or the beginning of a compression to the beginning of the next compression in a compressional wave . However,...

# data[].attributes.attachment_link.title
Physics Waves: Frequency & Wavelength FREE Science Lesson

# data[].attributes.attachment_link.description
Frequency is a measure of how many waves pass a point in a certain amount of time. The higher the frequency, the closer the waves are together and the greater the energy carried by the waves will...

# data[].attributes.attachment_link.description
Frequency is a measure of how many waves pass a point in a certain amount of time. The higher the frequency, the closer the waves are together and the greater the energy carried by the waves will...

# data[].attributes.attachment_link.readable_text
All waves transmit energy not matter.

A is a repeating disturbance or vibration that transfers or moves from place to place.

We depend on waves for nearly everything we do from talking, being able to see things with our eyes, listening to music and using a cell phone all require waves transmitting energy.

There are many different kinds of waves, but the o ne thing waves all have in common is they transmit and not matter.

What is a Medium ?

A is a material through which medium waves can travel. It can be a solid, liquid, or gas.

Some waves require particles of a "medium" to transmit the energy.

Types of Waves

Topic Tips

All waves transmit energy NOT matter.​

Some waves require a medium (solid, liquid, or gas particles) to transmit energy. Some waves do not.

There are two types of waves transverse waves and compressional/longitudinal waves. Each move the particles of the medium in different ways (parallel or perpendicular).

# data[].attributes.attachment_link.description
A wave is a repeating disturbance or vibration that transfers or moves energy from place to place. We depend on waves for nearly everything we do from talking, being able to see things with...

# data[].attributes.body
Amplitude

The height of a wave. Usually measured from the wave's resting point to the peak of the wave.

Wavelength

The distance between wave peaks. Usually measured from the peak of one wave to the peak of the wave next to it.

Energy

It makes things happen! (Or more formally: the ability to do work)

Wave Peak

The highest point on a wave. Also called the crest.

Sound Waves

Vibrations of air particles that transmit sound. Sound waves are a type of longitudinal wave.

Transverse Waves

When the disturbance moves perpendicular to the direction of the wave. Put simply: When a wave moves up and down.

Longitudinal Wave

When the disturbance moves parallel to the direction of the wave. Put simply: When a wave moves forward and back.

Particle

The smallest possible unit of matter.

# data[].attributes.attachment_caption
Transverse Wave: Matter moves back and forth at right angles to direction that waves travel.

# data[].attributes.headline
What are the types of waves? Transverse and Longitudinal. 

# data[].attributes.subject
What are the types of waves? Transverse and Longitudinal. 

# data[].attributes.headline
Wavelength, Frequency, Amplitude, Waves peed 

# data[].attributes.subject
Wavelength, Frequency, Amplitude, Waves peed 

# data[].attributes.attachment_link.readable_text
Section Learning Objectives

By the end of this section, you will be able to do the following:

Define amplitude, frequency, period, wavelength, and velocity of a wave

Relate wave frequency, period, wavelength, and velocity

Solve problems involving wave properties

Teacher Support

The learning objectives in this section will help your students master the following standards:

(7) Science concepts. The student knows the characteristics and behavior of waves. The student is expected to:

(B) investigate and analyze the characteristics of waves, including velocity, frequency, amplitude, and wavelength, and calculate using the relationship between wave speed, frequency, and wavelength;

(D) investigate the behaviors of waves, including reflection, refraction, diffraction, interference, resonance, and the Doppler effect.

Wave Variables

In the chapter on motion in two dimensions, we defined the following variables to describe harmonic motion:

Amplitude-maximum displacement from the equilibrium position of an object oscillating around such equilibrium position

Frequency-number of events per unit of time

Period-time it takes to complete one oscillation

For waves, these variables have the same basic meaning. However, it is helpful to word the definitions in a more specific way that applies directly to waves:

Amplitude-distance between the resting position and the maximum displacement of the wave

Frequency-number of waves passing by a specific point per second

Period-time it takes for one wave cycle to complete

In addition to amplitude, frequency, and period, their wavelength and wave velocity also characterize waves. The wavelength λ λ is the distance between adjacent identical parts of a wave, parallel to the direction of propagation. The wave velocity v w v w is the speed at which the disturbance moves.

Tips For Success

Wave velocity is sometimes also called the propagation velocity or propagation speed because the disturbance propagates from one location to another.

Consider the periodic water wave in Figure 13.7. Its wavelength is the distance from crest to crest or from trough to trough. The wavelength can also be thought of as the distance a wave has traveled after one complete cycle-or one period. The time for one complete up-and-down motion is the simple water wave's period T. In the figure, the wave itself moves to the right with a wave velocity v w. Its amplitude X is the distance between the resting position and the maximum displacement-either the crest or the trough-of the wave. It is important to note that this movement of the wave is actually the disturbance moving to the right, not the water itself; otherwise, the bird would move to the right. Instead, the seagull bobs up and down in place as waves pass underneath, traveling a total distance of 2 X in one cycle. However, as mentioned in the text feature on surfing, actual ocean waves are more complex than this simplified example.

Watch Physics

Amplitude, Period, Frequency, and Wavelength of Periodic Waves

This video is a continuation of the video "Introduction to Waves" from the "Types of Waves" section. It discusses the properties of a periodic wave: amplitude, period, frequency, wavelength, and wave velocity.

Tips For Success

The crest of a wave is sometimes also called the peak.

Grasp Check

If you are on a boat in the trough of a wave on the ocean, and the wave amplitude is 1 m, what is the wave height from your position?

1. 1 m

2. 2 m

3. 4 m

4. 8 m

The Relationship between Wave Frequency, Period, Wavelength, and Velocity

Since wave frequency is the number of waves per second, and the period is essentially the number of seconds per wave, the relationship between frequency and period is

or

just as in the case of harmonic motion of an object. We can see from this relationship that a higher frequency means a shorter period. Recall that the unit for frequency is hertz (Hz), and that 1 Hz is one cycle-or one wave-per second.

The speed of propagation v w is the distance the wave travels in a given time, which is one wavelength in a time of one period. In equation form, it is written as

or

From this relationship, we see that in a medium where v w is constant, the higher the frequency, the smaller the wavelength. See Figure 13.8.

Teacher Support

Teacher Support

[BL] For sound, a higher frequency corresponds to a higher pitch while a lower frequency corresponds to a lower pitch. Amplitude corresponds to the loudness of the sound.

[BL] [OL] Since sound at all frequencies has the same speed in air, a change in frequency means a change in wavelength.

[Figure Support] The same speaker is capable of reproducing both high- and low-frequency sounds. However, high frequencies have shorter wavelengths and are hence best reproduced by a speaker with a small, hard, and tight cone (tweeter), whereas lower frequencies are best reproduced by a large and soft cone (woofer).

These fundamental relationships hold true for all types of waves. As an example, for water waves, v w is the speed of a surface wave; for sound, v w is the speed of sound; and for visible light, v w is the speed of light. The amplitude X is completely independent of the speed of propagation v w and depends only on the amount of energy in the wave.

Snap Lab

Waves in a Bowl

In this lab, you will take measurements to determine how the amplitude and the period of waves are affected by the transfer of energy from a cork dropped into the water. The cork initially has some potential energy when it is held above the water-the greater the height, the higher the potential energy. When it is dropped, such potential energy is converted to kinetic energy as the cork falls. When the cork hits the water, that energy travels through the water in waves.

Large bowl or basin

Water

Cork (or ping pong ball)

Stopwatch

Measuring tape

Instructions

1. Fill a large bowl or basin with water and wait for the water to settle so there are no ripples.

2. Gently drop a cork into the middle of the bowl.

3. Estimate the wavelength and the period of oscillation of the water wave that propagates away from the cork. You can estimate the period by counting the number of ripples from the center to the edge of the bowl while your partner times it. This information, combined with the bowl measurement, will give you the wavelength when the correct formula is used.

4. Remove the cork from the bowl and wait for the water to settle again.

5. Gently drop the cork at a height that is different from the first drop.

6. Repeat Steps 3 to 5 to collect a second and third set of data, dropping the cork from different heights and recording the resulting wavelengths and periods.

7. Interpret your results.

Grasp Check

A cork is dropped into a pool of water creating waves. Does the wavelength depend upon the height above the water from which the cork is dropped?

1. No, only the amplitude is affected.

2. Yes, the wavelength is affected.

Teacher Support

Teacher Support

Students can measure the bowl beforehand to help them make a better estimation of the wavelength.

Virtual Physics

Wave on a String

In this animation, watch how a string vibrates in slow motion by choosing the Slow Motion setting. Select the No End and Manual options, and wiggle the end of the string to make waves yourself. Then switch to the Oscillate setting to generate waves automatically. Adjust the frequency and the amplitude of the oscillations to see what happens. Then experiment with adjusting the damping and the tension.

Grasp Check

Which of the settings-amplitude, frequency, damping, or tension-changes the amplitude of the wave as it propagates? What does it do to the amplitude?

1. Frequency; it decreases the amplitude of the wave as it propagates.

2. Frequency; it increases the amplitude of the wave as it propagates.

3. Damping; it decreases the amplitude of the wave as it propagates.

4. Damping; it increases the amplitude of the wave as it propagates.

Solving Wave Problems

Worked Example

Calculate the Velocity of Wave Propagation: Gull in the Ocean

Calculate the wave velocity of the ocean wave in the previous figure if the distance between wave crests is 10.0 m and the time for a seagull to bob up and down is 5.00 s.

Strategy

The values for the wavelength (λ=10.0 m)(λ=10.0 m) and the period (T=5.00 s) (T=5.00 s) are given and we are asked to find v w v w Therefore, we can use v w= λ T v w= λ T to find the wave velocity.

v w= 10.0 m 5.00 s=2. 00 m/s. v w= 10.0 m 5.00 s=2. 00 m/s.

This slow speed seems reasonable for an ocean wave. Note that in the figure, the wave moves to the right at this speed, which is different from the varying speed at which the seagull bobs up and down.

Worked Example

Calculate the Period and the Wave Velocity of a Toy Spring

The woman in Figure 13.3 creates two waves every second by shaking the toy spring up and down. (a)What is the period of each wave? (b) If each wave travels 0.9 meters after one complete wave cycle, what is the velocity of wave propagation?

Strategy FOR (A)

To find the period, we solve for T= 1 f T= 1 f , given the value of the frequency (f=2 s −1). (f=2 s −1).

T= 1 2 s −1 =0. 5 s. T= 1 2 s −1 =0. 5 s.

Strategy FOR (B)

Since one definition of wavelength is the distance a wave has traveled after one complete cycle-or one period-the values for the wavelength (λ=0.9 m)(λ=0.9 m) as well as the frequency are given. Therefore, we can use v w=f λ v w=f λ to find the wave velocity.

We could have also used the equation v w= λ T v w= λ T to solve for the wave velocity since we already know the value of the period (T=0.5 s) (T=0.5 s) from our calculation in part (a), and we would come up with the same answer.

Practice Problems

Check Your Understanding

Teacher Support

Teacher Support

Use these questions to assess students' achievement of the section's Learning Objectives. If students are struggling with a specific objective, these questions will help identify such objective and direct them to the relevant content.

10 .

What is meant by the wavelength of a wave?

1. The wavelength is the distance between adjacent identical parts of a wave, parallel to the direction of propagation.

2. The wavelength is the distance between adjacent identical parts of a wave, perpendicular to the direction of propagation.

3. The wavelength is the distance between a crest and the adjacent trough of a wave, parallel to the direction of propagation.

4. The wavelength is the distance between a crest and the adjacent trough of a wave, perpendicular to the direction of propagation.

11 .

How can you mathematically express wave frequency in terms of wave period?

1. f= 1 T

2. f= ( 1 T)2

3. f=T

4. f= (T)2

# data[].attributes.attachment_link.title
13.2 Wave Properties: Speed, Amplitude, Frequency, and Period - Physics | OpenStax

# data[].attributes.attachment_link.description
Section Learning Objectives By the end of this section, you will be able to do the following: Define amplitude, frequency, period, wavelength, and velocity of a wave Relate wave frequency, period, wavelength, and velocity Solve problems involving wave properties Teacher Support The learning objectives in this section will help your students master the following standards: (7) Science concepts.

# data[].attributes.attachment_caption
Matter in medium moves in the same direction that wave travels. (Parallel Motion) Lines never intersect. 

# data[].attributes.attachment_caption
They both require a MEDIUM, which is matter. 

# data[].attributes.headline
Longitudinal Waves and Transverse waves are MECHANICAL WAVES.  

# data[].attributes.subject
Longitudinal Waves and Transverse waves are MECHANICAL WAVES.  

# data[].attributes.headline
Compression and Longitudinal Waves Explained. 

# data[].attributes.subject
Compression and Longitudinal Waves Explained. 

# data[].attributes.attachment_link.description
Compressional and longitudinal waves describe waves that vibrate by pushing together and moving apart parallel to the direction in which the wave travels. Compressional and longitudinal waves are two...

# data[].attributes.attachment_link.description
Join an activity with your class and find or create your own quizzes and flashcards.