ASEI Lesson Plan on Physics

Lesson Note on Wave Motion


Subject: Physics
Theme: Waves
Topic: Wave Motion
Sub Topic: Wave Motion
Date: dd/mm/yyyy
Class: S.S.S 2
Duration: 50 Minutes
No of Learners: 30

Learning Objectives:

By the end of the lesson learners should be able to:
  1. Identify and Define a wave.


    1. A wave transfers energy from one place to another without the transfer of particles in the medium. Rather, individual particles vibrate (oscillate) at fixed positions instead.
    2. A wave is a disturbance which travels outward from its source, carrying energy along with it.
    3. Wave motion can also be defined as a process of transferring disturbance (in form of kinetic energy) from one point to another in a medium without any transfer of particles of the medium.
    4. Wave motion can be defined as a disturbance which travels through a medium transferring energy from one point to another without causing any permanent displacement of the medium.

  2. Explain Mechanical waves and Electromagnetic waves.

    1. Mechanical waves are those waves that require a material medium for their propagation.
      Examples of such waves are water waves, sound waves, and waves on a rope or string.
    2. Electromagnetic waves are waves that do not require a material medium for propagation. Examples are light waves, radio waves, X-rays and gamma rays.
  3. Explain Stationary waves, progressive waves and the types of progressive (travelling) waves.

    1. Stationary wave:
      Waves which appear to be vibrating vertically without travelling horizontally created from waves with identical frequency and amplitude interfering with one another while travelling in opposite directions.
      Examples of standing waves are; waves generated by piano, guitar string, two people shaking a jump rope, etc.
    2. Progressive Wave:

      A wave which continues to spread out transferring energy from the source of disturbance is called a progressive wave.
      Progressive waves have properties such as wavelength, height, amplitude, velocity, frequency, and period. Examples of progressive waves are sound waves, seismic waves, and water waves.

    There are two types of progressive waves.

    1. Transverse waves: are waves which travel perpendicularly to the direction of the vibrations producing the waves. That is, a transverse wave is one in which the particle displacements are perpendicular to the direction along which the wave travels. The water wave is a transverse wave since the up-and-down (vertical) motion of the water particles is perpendicular to the direction of wave propagation (horizontal, along the wave surface). Other examples are; light waves, radio waves and wave produced in a rope.


    2. A longitudinal wave: is one in which the particle displacements are parallel to the direction along which the wave travels. That is, longitudinal waves are waves which travel in a direction parallel to the vibrations of the medium. The sound wave is an example of a longitudinal wave.


  4. Explain the graphic representation of a wave.

  5. Both transverse and longitudinal waves are represented by a sine curve.


  6. Explain the terms used in describing a wave.

    The dots on the graph represent the positions of the particles at that instant and the arrows indicate the direction of motion of these particles.



    1. Phase: Particles which are at the same verticle distances from their positions of rest and are moving in the same direction are said to be in the same phase. Particles A, C and E are in phase.
    2. A Cycle: is a complete to-and-fro movement or direction of a vibrating particle.
    3. Crest: This is the highest point on the wave.
    4. Trough: This is the lowest point on the wave.
    5. A Node: A node is a point on a stationary wave where there is no movement of the medium. That is a point at which the amplitude of vibration in the standing wave system is zero. The nodes are λ/2 apart.
    6. An antinode: Is a point on a stationary wave where there is the maximum displacement of the medium. Antinodes are λ/2 apart.
    7. Amplitude (A): This is the maximum displacement of a particle from its resting position. It is measured in metres.
    8. Wavelength (λ): This is the distance between two successive crests or successive troughs (or two successive points in phase) of the wave. It is measured in metres.
    9. Wavefronts: Can be represented as lines which are always perpendicular to the direction of wave travel. The distance between one wavefront to the next is the wavelength.
    10. Frequency (f):This is the number of complete vibrations or cycles that a particle makes in one second. It is also equivalent to the number of complete waves passing at a given point in one second. The S.I unit of frequency is the Hertz (Hz) which is defined as one cycle or oscillation per second (1 cps).
      The frequency of a wave is identical to the frequency of the source that sends it out.
    11. Period (T): This is the time taken by a wave-particle to make one complete oscillation. It is measured in seconds. The period is also the time taken by the wave to travel one wavelength.

      The period (T) and frequency (f) are related by
      f = 1/T or
      T = 1/f

    12. Wave Speed or velocity (v): This is the distance the wave travels in one second. Its unit is metre-per-second (m/s)
  7. Write and express the Mathematical Relationships between Frequency (f), Wavelength (λ) and Velocity (v).

    Velocity = Frequency x Wavelength
    v = fλ ----------- (1)
    But f = 1/T
    Hence v = λ/T
    λ = vT ----------- (2)

  8. Write the Mathematical Representation of Wave Motion - Progressive Wave.


  9. List and explain the properties of waves:

    The properties of waves include; Reflection, Refraction, Interference, Diffraction, and Polarization.
    1. Reflection of waves:
    2. Waves are reflected upon encountering a barrier. If the barrier is plane, the angle of incidence is equal to the angle of reflection. The frequency, speed and wavelength of the waves remain unchanged as long as they remain in the same medium after reflection.
      Law of Reflection: When a wave strikes an interface, the angle of incidence measured to the normal of the interface is equal to the angle of reflection.

    3. Refraction of wave:
    4. Refraction is the change in the speed and direction of the waves as they cross the boundary between two media of different densities.
      The wave travels more slowly in shallow water compared to deep water.
      The angle of incidence (i) is the angle the direction of the incident wavefront makes with the normal at the boundary surface. The angle of refraction (r) is the angle the direction of the refracted ray makes with the normal to the plane boundary.
      N/B. The wavelength decreases and the direction shift as the wave hit the more shallow side.
      N/B. The amount by which a wave is refracted by a material is given by the refractive index of the material. The directions of incidence and refraction are related to the refractive indices of the two materials by Snell's law.
    5. Diffraction of wave:
    6. Diffraction is the ability of waves to bend around obstacles in their path. A wave exhibits diffraction when it encounters an obstacle that bends the wave or when it spreads after emerging from an opening. The amount of diffraction depends on the wavelength of the wave compared with the size of the gap. That is, Diffraction effects are more pronounced when the size of the obstacle or opening is comparable to the wavelength of the wave.
    7. Interference of wave:
      When two or more waves meet, they interact with each other. The interaction of waves with other waves is called wave interference.Wave interference may occur when two waves that are traveling in opposite directions meet.Interference is the effect produced when two waves of the same frequency, amplitude and wavelength traveling in the same direction in a medium are superposed - as they simultaneously pass through a given point. The two waves pass through each other, and this affects the amplitude. How amplitude is affected by wave interference depends on the type of interference. Interference can be constructive or destructive.
      1. Constructive Interference:
      2. Constructive interference occurs when the crests of one wave overlap the crests of the other wave. As the waves pass through each other, the crests combine to produce a wave with greater amplitude.
      3. Destructive Interference:
      4. Destructive interference occurs when the crests of one wave overlap the trough of another wave. As the waves pass through each other, the crests and troughs cancel each other out to produce a wave with zero amplitude.
        The task of determining the shape of the resultant demands that the principle of superposition is applied. The principle of superposition is sometimes stated as follows:

        When two waves interfere, the resulting displacement of the medium at any location is the algebraic sum of the displacements of the individual waves at that same location.

        Displacement of Pulse ADisplacement of Pulse BResulting DisplacementDisplacement of Pulse A and B = Resulting Displacement
        +1+1+2
        -1-1-2

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        +1-10
        +1-2-1
        +2-1+1
    8. Polarization of Wave:
    9. A light wave that is vibrating in more than one plane is referred to as unpolarized light. Light emitted by the sun, by a lamp in the classroom, or by a candle flame is unpolarized light. Such light waves are created by electric charges that vibrate in a variety of directions, thus creating an electromagnetic wave that vibrates in a variety of directions.
      In general, it is helpful to picture unpolarized light as a wave that has an average of half its vibrations in a horizontal plane and half of its vibrations in a vertical plane.

      It is possible to transform unpolarized light into polarized light. Polarized light waves are light waves in which the vibrations occur in a single plane. The process of transforming unpolarized light into polarized light is known as polarization.
      1. Types of Polarization:
        • Linear Polarization:
        • In linear polarization, the electric field of light is limited to a single plane along the direction of propagation.
        • Circular Polarization:
        • There are two linear components in the electric field of light that are perpendicular to each other such that their amplitudes are equal, but the phase difference is ∏/2.
          The propagation of the occurring electric field will be in a circular motion.
        • Elliptical Polarization:
        • The electric field of light follows an elliptical propagation. The amplitude and phase differences between the two linear components are not equal.


  10. List methods Used in the Polarization of Light

    1. Polarization by Transmission
    2. Polarization by Reflection
    3. Polarization by Scattering
    4. Polarization by Refraction
  11. Explain Applications of Polarization.

    1. Polarization is used in sunglasses to reduce glare.
    2. Polaroid filters are used in plastic industries for performing stress analysis tests.
    3. Three-dimensional movies are produced and shown with the help of polarization.
    4. Polarization is used for differentiating between transverse and longitudinal waves.
    5. Infrared spectroscopy uses polarization.
    6. It is used in seismology to study earthquakes.
    7. In Chemistry, the chirality of organic compounds is tested using polarization techniques.
  12. Solve problems on a wave.





Rationale:

Waves are everywhere. Whether we recognize it or not, we encounter waves daily. Sound waves, visible light waves, radio waves, microwaves, water waves, sine waves, cosine waves, stadium waves, earthquake waves, waves on a string, and slinky waves are just a few examples of our daily encounters with waves. waves play a significant role in life because they transfer energy and waves allow for long-range communication via mobile phones, television and radio. sound is waves, pressure waves that travel in air or other fluids or solids. We use sound to hear things, to communicate, and ultrasound (sound too high a frequency to hear) to diagnose illnesses, or to look inside solid materials for flaws, and probably a lot more things. Then there are electromagnetic waves, which are used for radio broadcasting and communications, cellphones, RF remote controls, measuring distances and location (GPS), and even for learning about space by analyzing radio frequency waves coming from galaxies and stars. XRays are radio waves that are just a lot higher frequency. They are called 'ionizing radiation' because they can strip electrons from individual atoms. Light is also a wave (or a particle, depending on how you're talking about it). Light is an electromagnetic wave, like radio waves and X-rays but even higher frequency. Without light, we couldn't see. Also, all the energy that comes to earth is light from the sun, which plants use to make oxygen for us to breathe and food for us to eat. Also, lasers are used for millions of things these days, from surgery to welding metal and plastic, for measuring, communications, targetting munitions, etc. Then there are ocean waves. Useful for surfing.

Prerequisite/ Previous knowledge:

  • Newton's Law of Motion
  • Physical Wave

Learning Materials:

Demo of water wave, diagram of a wave, tape, string, stopwatches, chart paper, basin, water, guitar, markers.

Reference Materials:

  • New School Physic for Senior Secondary Schools, by M. W. Anyakowa.
  • Lamlas's SSCE and UTME, by O. Ajaja and H. B. Olaniyi


Lesson Development:

STAGETEACHER'S ACTIVITYLEARNER'S ACTIVITYLEARNING POINTS
INTRODUCTION
full class session (5mins)
The teacher asks learners to state Newton's first law of motion.

Learners' response to teacher's question.

Newton's first law of motion states that every object continues in its state of rest or uniform motion in a straight line unless acted upon by an external force.

Confirming previous knowledge.
INTRODUCTORY ACTIVITY
full class session (5mins)
The teacher provides learners with a basin full of water and asks learners the following questions:
  • What is the state of the medium?
  • What is the state of the medium when a stone or a finger is deep into the medium?

Learners respond to teacher's questions

  • The media was calm.
  • The media was disturbed, and this led to the generation of ripple/ waves.
.

Developing the idea of wave motion.
Development 1.
(2 minutes)

The teacher tells learners to relate the observation above to define waves in their own words.

Learners' expected response.
  1. A wave is a disturbance which travels outward from its source, carrying energy along with it.
  2. Wave motion can also be defined as a process of transferring disturbance (in form of kinetic energy) from one point to another in a medium without any transfer of particles of the media.
Meaning of wave
Stage 2
(5 minutes)
Divide students into small groups and provide each group with tape, string, stopwatches, chart paper, and markers.
The teacher explains different forms/types of disturbance that generate waves, this includes;
  1. electromagnetic radiation travelling in a vacuum and glass, sound waves travelling through air and water, seismic waves travelling through the Earth
  2. mechanical disturbance travelling through the string, rope, fluid.


The teacher asks learners to define/explain mechanical waves and electromagnetic waves in their own words.
Learners expected respond
  1. Mechanical waves are those waves that require a material medium for their propagation.
    Examples of such waves are water waves, sound waves, and waves on a rope or string.
  2. Electromagnetic waves are waves that do not require a material medium for propagation. Examples are light waves, radio waves, X-rays and gamma rays.
Mechanical and Electromagnetic waves.
Stage 3
(5 minutes)
The teacher divides students into small groups and provides each group with tape, string, stopwatches, chart paper, basin, water, stone, guitar and markers.


The teacher asks learners to state their observations in each activity.



The teacher prompts learners to explain stationary waves, progressive waves and the types of progressive (travelling) waves based on their observation of the ACTIVITIES.


Stationary wave: Waves which appear to be vibrating vertically without travelling horizontally created from waves with identical frequency and amplitude interfering with one another while travelling in opposite directions.
Examples of standing waves are; waves generated by piano, guitar string, two people shaking a jump rope, etc.

Progressive Wave: A wave which continues to spread out transferring energy from the source of disturbance is called a progressive wave.
Progressive waves have properties such as wavelength, height, amplitude, velocity, frequency, and period. Examples of progressive waves are sound waves, seismic waves, and water waves.
  1. ACTIVITY ONE: The learners use the string to create waves. The learners tape one end of a piece of string (about two feet long) to a desk. The learners pull the string so it is tight, but lays flat against the desk. The learners take turns holding the end of the string and moving it right to left to produce a wave. The learners move the string fast and slow and observed the movement of the wave and draw pictures of the waves they see.
  2. ACTIVITY TWO: The learners fill a basin with water and allow the medium to settle/calm, thereafter, dip a finger into the water and observed the disturbance/wave that was generated and the direction of flow/movement of the wave.
  3. ACTIVITY THREE: The learners engage in skipping rope exercises and observe the direction and movement of the wave.
  4. ACTIVITY FOUR: The learners pluck/strum the guitar string and observed the direction and movement of the wave.


The learners state their observations
  1. ACTIVITY ONE: The direction of the disturbance of the wave and the direction of the flow of the wave itself moves in the same direction.
  2. ACTIVITY TWO: The direction of the disturbance of the wave and the direction of the flow of the wave itself moves in a different direction.
  3. ACTIVITY THREE: There is no direction of flow of the wave, however, there is an up and down movement of the wave.
  4. ACTIVITY FOUR: There is no direction of flow of the wave, however, there is an up and down movement of the wave.
Stationary waves, progressive waves and the types of progressive (travelling) waves.
The teacher explains to learners that there are two types of progressive/travelling wave and guide learners to list and explain the types of progressive waves based on the activities above.Learners are expected to respond.
The two types of progressive waves are the Tranverse wave and longitudinal wave.
  1. Transverse waves: are waves which travel perpendicularly to the direction of the vibrations producing the waves. That is, a transverse wave is one in which the particle displacements are perpendicular to the direction along which the wave travels. The water wave is a transverse wave since the up-and-down (vertical) motion of the water particles is perpendicular to the direction of wave propagation (horizontal, along the wave surface). Other examples are; light waves, radio waves and wave produced in a rope.
  2. A longitudinal wave: is one in which the particle displacements are parallel to the direction along which the wave travels. That is, longitudinal waves are waves which travel in a direction parallel to the vibrations of the medium. The sound wave is an example of a longitudinal wave.
Step 4:
(10 mins)
The Teacher show students a diagram of a wave, and a graphic representation of a wave and discuss the different parts of a wave including Crest, Trough, Amplitude, Wavelength, Frequency,
Define 'frequency' and discuss how to calculate frequency.
The teacher guides learners to explain each of the wave terms above.

Learners expected answers.
  1. Phase: Particles which are at the same verticle distances from their positions of rest and are moving in the same direction are said to be in the same phase. Particles A, C and E are in phase.
  2. A Cycle: This is a complete to-and-fro movement or direction of a vibrating particle.
  3. Crest: This is the highest point on the wave.
  4. Trough: This is the lowest point on the wave.
  5. A Node: A node is a point on a stationary wave where there is no movement of the medium. That is a point at which the amplitude of vibration in the standing wave system is zero. The nodes are λ/2 apart.
  6. An antinode: Is a point on a stationary wave where there is the maximum displacement of the medium. Antinodes are λ/2 apart.
  7. Amplitude (A): This is the maximum displacement of a particle from its resting position. It is measured in metres.
  8. Wavelength (λ): This is the distance between two successive crests or successive troughs (or two successive points in phase) of the wave. It is measured in metres.
  9. Wavefronts: Can be represented as lines which are always perpendicular to the direction of wave travel. The distance between one wavefront to the next is the wavelength.
  10. Frequency (f): This is the number of complete vibrations or cycles that a particle makes in one second. It is also equivalent to the number of complete waves passing at a given point in one second. The S.I unit of frequency is the Hertz (Hz) which is defined as one cycle or oscillation per second (1 cps). The frequency of a wave is identical to the frequency of the source that sends it out.
  11. Period (T): This is the time taken by a wave-particle to make one complete oscillation. It is measured in seconds. The period is also the time taken by the wave to travel one wavelength.

    The period (T) and frequency (f) are related by
    f = 1/T or
    T = 1/f

  12. Wave Speed or velocity (v): This is the distance the wave travels in one second. Its unit is metre-per-second (m/s)
Terms used in describing a wave.
Step 5
10 mins
The teacher explains an expression for the Mathematical Relationships between Frequency (f), Wavelength (λ) and Velocity (v) and the Mathematical representation of progressive wave motion.

Velocity = Frequency x Wavelength
v = fλ ----------- (1)
But f = 1/T
Hence v = λ/T
λ = vT ----------- (2)

The teacher guide learners to derive the mathematical equation of the wave.
Learners follow the teacher's explanation to derive the mathematical equation of the wave.

Mathematical Relationships between Frequency (f), Wavelength (λ) and Velocity (v).

Mathematical Representation of Wave Motion - Progressive Wave.
Step 6
5 mins
The teacher asks learners to list and explain the properties of waves, that is, the directions a wave can follow if encountering a barrier.

The teacher gives learners a prompt according to Newton's first law of motion, "every object continues in its state of rest or uniform motion in a straight line unless acted upon by an external force". This means that running water that is flowing with uniform acceleration on a straight line, or a ray of light moving in one direction can be diverted or slowed down by an external force which could be a barrier using mirrors and lenses to experiment with reflection and refraction of the wave.

Show learners a diagram of a wave. Guide learners to discuss the different physical properties of a wave including:
  1. Reflection
  2. Refraction
  3. Interference
  4. Diffraction
  5. Polarization
Learners expected responses.
Wave can be reflected, refracted, interference, diffracted and polarized by external forces/barriers.
  1. Reflection: Change in the direction of propagation of a wave that strikes a boundary between different media through which it cannot pass.

    When a wave strikes such a boundary it bounces back or is reflected, just as a ball bounces off the floor. The angle of incidence is the angle between the path of the wave and a line perpendicular to the boundary. The angle of reflection is the angle between the same line and the path of the reflected wave. All reflected waves obey the law of reflection, which states that the angle of reflection is equal to the angle of incidence. The reflectivity of a material is the fraction of energy of the oncoming wave that is reflected by it.
  2. Refraction: Change in direction of a wave as it leaves one medium and enters another.

    Waves, such as sound and light waves, travel at different speeds in different media. When a wave enters a new medium at an angle of less than 90°, the change in speed occurs sooner on one side of the wave than on the other, causing the wave to bend, or refract. When water waves approach shallower water at an angle, they bend and become parallel to the shore. Refraction explains the apparent bending of a pencil when it is partly immersed in water and viewed from above the surface. It also causes the optical illusion of the mirage.
  3. Diffraction: Change in the directions and intensities of a group of waves after passing by an obstacle or through an aperture.

    It can also be defined as the process by which a beam of light or other systems of waves is spread out as a result of passing through a narrow aperture or across an edge.
  4. Interference: The disturbance that results when two WAVES come together at a single POINT in space; the disturbance is the sum of the contribution of each wave. For example, if two crests of identical waves arrive together, the net disturbance will be twice as large as each incoming wave; if the crest of one wave arrives with the trough of another, there will be no disturbance at all. One common example of interference is the appearance of dark bands when light is viewed through a window screen.

    1. Constructive interference occurs if two components have the same frequency and phase; the wave amplitudes are reinforced.
    2. Destructive interference occurs when the two waves are out of phase by one-half period (see the periodic motion); if the waves are of equal amplitude, they cancel each other. Two waves moving in the same direction but having slightly different frequencies interfere constructively at regular intervals, resulting in a pulsating frequency called a beat. Two waves travelling in opposite directions but having equal frequencies interfere constructively in some places and destructively in others, resulting in a standing wave.
  5. Polarization: the phenomenon in which waves of light or other radiation are restricted in direction of vibration.

    Unpolarized light consists of waves moving in the same direction with their electric vectors pointing in random orientations about the axis of propagation. Plane-polarized light consists only of waves that vibrate in one direction. In circular polarization, the electric vector rotates about the propagation direction. Light may be polarized by reflection or by passing it through polarizing filters, such as certain crystals, that transmit vibrations in one plane but not in others. Polarized light has useful applications in crystallography, liquid-crystal displays, optical filters, and the identification of optically active chemical compounds.
Physical properties of a wave.

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Step 7
5 mins
The teacher guides learners to list methods used in the polarization of light.Learners expected method.
  1. Polarization by Transmission
  2. Polarization by Reflection
  3. Polarization by Scattering
  4. Polarization by Refraction
The method used in the polarization of light.
Step 8
5 mins
The teacher guides learners to list the application of polarization.Learners expected method.
  1. Polarization is used in sunglasses to reduce glare.
  2. Polaroid filters are used in plastic industries for performing stress analysis tests.
  3. Three-dimensional movies are produced and shown with the help of polarization.
  4. Polarization is used for differentiating between transverse and longitudinal waves.
  5. Infrared spectroscopy uses polarization.
  6. It is used in seismology to study earthquakes.
  7. In Chemistry, the chirality of organic compounds is tested using polarization techniques.
Application of polarization.
EVALUATION
10 mins
The teacher asks questions to the learners to evaluate the lesson.
  1. Explain the terms. frequency, wavelength, velocity, and period as applied to wave motion.
  2. Sketch a waveform and label the amplitude, wavelength, crest and trough. What is the relationship between wavelength, frequency and velocity?
  3. What is wave motion?
  4. How do you understand the interference of waves?
    Distinguish between constructive interference and destructive interference.
  5. A wave sent out from a source is reflected by the source in 1.0 x 10^-3 sec. If the velocity of the wave is 3.0 x 10^8 m/sec, what is the distance of the reflecting surface from the source?
  6. What is the distance between a node and an antinode for a transverse wave?
  7. The equation y = a sin (wt - kx) represents a plane wave travelling in a medium along the x-direction, y being the displacement at the point x at time t.
    1. Given that x is in metres and t is in seconds, state the units of k and w.
    2. What physical quantity does w/k represent? Justify your answer.
    3. State whether the wave is travelling in the positive or negative x-direction.
The learners answer the teacher's questions. Ask the learners questions to assess the achievement of the set objectives.
CONCLUSION
2mins
The teacher asks learners to use the figure above to answer the questions below.
  1. If the frequency of waveform A is 60 Hz, what is the period of waveform B?
  2. What is the number of type-B waves passing a given point in the medium in 5 sec?
  3. If the speed of the waves is 5 m/s, calculate the distance between two successive particles of waveform-A which are in phase.
Learners conclude the lesson
  1. Period of A = 1/60 sec
    Period of B = 3/2 x period of A
    Period of B = 3/2 x 1/60
    Period of B = 1/40 sec, or 0.025 sec.
  2. Frequency of B = 0.025 = 40 Hz,
    i.e. 40 waves pass any given point in one second, or 200 waves in 5 sec.
  3. The required distance is the wavelengthλ = v/f
    Therefore, the wavelength = (500/60)cm, or 8.33cm
Application: calculation of the wave concept.
ASSIGNMENTThe teacher gives learners a take home.
  1. A vibrating plate is used to generate waves in a pool of water. The distance between successive troughs is 7cm and a crest travels from the vibrator to the edge of the pool, 52.5cm away, in 2.5 sec. Calculate the frequency of the vibrator.
  2. A rarefaction and an adjacent compression of a sound wave travelling in the air are separated by a distance of 15cm. If the velocity of sound in air is 330 m/s. What is the frequency?
  3. If the speed of sound in air is 340 m/s, what is the period of vibration of sound waves of wavelength 1.7m?
  4. Which of the following phenomena does not apply to longitudinal waves?
    • interference
    • refraction
    • diffraction
    • polarization
  5. Which of the following waves is both mechanical and transverse?
    • radio
    • sound
    • water
    • x-rays
  6. What is the frequency of a wave having a wavelength of 20cm and a velocity of 0.5 m/s?
  7. An anchored boat is hit by water crests every 5sec. If the wave crests are 60m apart, What is the velocity of the wave?
Improving their level of understanding of waves.

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