CLASS 11 | ONE SHOT | WAVES | Physics | NEET 2024 | Xylem NEET Tamil

01:52:14
https://www.youtube.com/watch?v=db0tlXybDgg

Summary

TLDRIn this physics lecture, the instructor covers different aspects of waves, including their types, propagation, and associated physical phenomena. The lecture begins by listing various wave types, such as progressive, standing, string, transverse, and longitudinal waves. It then delves into wave dimensions, discussing one-dimensional (string waves), two-dimensional, and three-dimensional wave propagation, including practical examples like sound and light waves (electromagnetic). The instructor explains the mechanics behind mechanical and non-mechanical waves, emphasizing the need for a medium in mechanical ones. The lecture describes how waves transfer energy, momentum, and information without matter movement. Key terminologies like wavelength, velocity, frequency, and time periods are explained, along with their interrelations. It highlights how velocity is proportional to wavelength, while frequency depends on the source. The session further examines the mathematical expressions for wave motion and stresses on understanding physics formulas. Reflection, transmission, and the behaviors of waves at different medium boundaries are reviewed, showing how they affect wave properties. Standing waves are introduced, alongside explanations of nodes and anti-nodes, maximum and minimum displacement points. The instructor discusses sound wave applications in musical instruments, illustrating practical uses of these physics concepts. In conclusion, the lecture emphasizes revision of key concepts, understanding mathematical formulations, and applying this knowledge to solve problems related to waves, their properties, and behaviors in different situations.

Takeaways

  • 📚 Understanding the fundamental properties of waves helps solve complex physics problems.
  • 🌊 Waves depict different physical phenomena and require different mediums for propagation.
  • 🔄 Reflection and transmission are key to understanding wave interactions at boundaries.
  • 🎸 Practical applications are extensive, notably in musical instruments and communication technologies.
  • 🔬 Studying wave equations and their components, like frequency and wavelength, is crucial.
  • ✅ Mastery of terms like nodes, anti-nodes, amplitude, and wavelength aids in grasping wave behavior.
  • 🎯 Mechanical and non-mechanical waves differ fundamentally, crucial for physics applications.
  • 💡 Concepts of wave energy transfer without mass movement are vital in physics.
  • 🧮 Formulas related to wave velocity and propagation are critical for theoretical problem-solving.
  • 🎓 Application in physics experiments requires a solid grasp of wave-related principles.

Timeline

  • 00:00:00 - 00:05:00

    The video begins with an enthusiastic greeting to the viewers, emphasizing a motivational spirit for learning and growth together. The host expresses gratitude for the engagement throughout 14 chapters of content, introducing the new topic of waves, stressing its importance and outlining key concepts such as wave types, terminologies, and characteristics.

  • 00:05:00 - 00:10:00

    The discussion focuses on the fundamental concept of waves and their significance in transferring energy, momentum, and information. Different wave types like transverse and longitudinal waves are introduced, explaining their propagation methods without matter transfer. This introduction serves as a basis for understanding complex wave interactions.

  • 00:10:00 - 00:15:00

    Understanding oscillations is recommended as a prerequisite, and the session continues to explore one-dimensional waves, highlighting string waves as examples. The expansion into two-dimensional and three-dimensional wave concepts is outlined, showcasing examples like sound waves and electromagnetic waves, setting the stage for deeper exploration.

  • 00:15:00 - 00:20:00

    Classification of waves is discussed in detail with emphasis on velocity, frequency, and wavelength. Mechanical and non-mechanical waves are differentiated, with mechanical ones requiring a medium. Examples such as sound waves (mechanical) and light waves (non-mechanical) reinforce the understanding of medium dependency.

  • 00:20:00 - 00:25:00

    The session explores wave propagation types, particularly transverse and longitudinal waves. Emphasis is placed on particle movement directions and the forces involved, like tension in strings affecting longitudinal wave properties. The segmentation aims to clarify distinctions between mechanical and non-mechanical waves and their propagation traits.

  • 00:25:00 - 00:30:00

    A summary of key distinctions between transverse and longitudinal waves is provided, highlighting compression, rarefaction, and the mechanical nature of sound waves. Important terms include resonance and amplitudes, with practical insights into their impacts on wave behavior. This sets a foundation for understanding subsequent concepts of wave behavior in different mediums.

  • 00:30:00 - 00:35:00

    The discussion delves into wave characteristics terminology, covering aspects like wavelength, frequency, and amplitude. The relationship between variables is emphasized, showcasing how varying them affects wave properties and their interactions with mediums. This serves as a groundwork for understanding wave equations and motion calculations.

  • 00:35:00 - 00:40:00

    Time period and frequency are clarified, illustrating how they define wave cycles and motions. The video explores complex relationships like angular frequency and wave velocity. Insight into how these metrics quantify wave characteristics aids in understanding their mathematical representations and real-world applications.

  • 00:40:00 - 00:45:00

    The relationship between oscillation positions, velocity, acceleration, and energy is covered. Concepts like potential and kinetic energy variations during wave motion are discussed. This offers a deeper insight into mechanical energy transformations and the role of oscillation extremes in wave dynamics, emphasizing the importance of energy conservation.

  • 00:45:00 - 00:50:00

    The session explains progressive wave development, focusing on equations that depict their motion. Formulae related to displacement, velocity, and sinusoids are introduced, with emphasis on expression derivations. This mathematical explanation provides essential details for constructing and analyzing wave functions and dynamics.

  • 00:50:00 - 00:55:00

    Further understanding is provided on wave expressions and important equations that depict wave motion. Emphasis is placed on displacement and velocity relationships. This segment forms the core understanding necessary for progressing into deeper aspects of wave physics, aiding in subsequent lessons and applications.

  • 00:55:00 - 01:00:00

    The intricacies of wave slope calculation, particle velocity, and their impact on wave propagation are analyzed. These calculations are vital for comprehending wave dynamics and for predicting wave behavior in practical scenarios. The introduction of particle velocity expressions adds depth to mechanical wave understanding.

  • 01:00:00 - 01:05:00

    A detailed look into string wave velocity is offered, taking into account string tension and medium properties. The relationship between tension, density, and wave velocity is emphasized, showcasing how they converge to define wave speed. This segment provides practical insights into medium-specific wave behaviors affecting engineering and scientific applications.

  • 01:05:00 - 01:10:00

    Energy intensity in string waves is introduced, linking factors like string density, velocity, and amplitude in power calculations. Such concepts are pivotal for understanding wave energy transfer across mediums, and for designing systems reliant on wave dynamics. Insights into intensity calculation deepen understanding of waves' practical applications.

  • 01:10:00 - 01:15:00

    The video examines wave reflection and transmission, detailing behavior between different media like rarer and denser substances. Critical understanding of these dynamics is essential for applied physics and engineering contexts, enhancing the ability to predict wave interaction outcomes in technological and natural settings.

  • 01:15:00 - 01:20:00

    Reflection and transmission phenomena are analyzed concerning shifts and amplitude changes across media interfaces. Real-world applications in optics and acoustics are highlighted, emphasizing how wave interaction with different mediums influences design and technology. Understanding frequency and wave transmission aids in engineering efficient systems.

  • 01:20:00 - 01:25:00

    The session transitions into standing waves, explaining their fixed nodes and varying amplitude characteristics. The conceptual framework explains wave superposition, standing wave creation, and energy conservation principles, essential for understanding phenomena such as resonances in physical systems and instrument design.

  • 01:25:00 - 01:30:00

    Discussion centers on standing wave characteristics, emphasizing fixed nodes and variable amplitudes, resulting in standing patterns. The mathematical expression for amplitude is given, aiding in the analysis of wave interactions and providing practical applications for technologies relying on wave mechanics, such as music and communication systems.

  • 01:30:00 - 01:35:00

    In this segment, a thorough explanation of practical wave applications highlights musical instruments. Concepts like fundamental frequency, harmonics, and overtone structures in instruments reveal the intersections of physics, engineering, and music. Detailed examples illustrate how theoretical wave principles manifest in everyday technology.

  • 01:35:00 - 01:40:00

    The exploration of open and closed pipe scenarios in waves advances knowledge about harmonics and resonance. Detailed discussions on standing waves in these contexts provide crucial insights into acoustic design and audio engineering, emphasizing how fundamental frequencies and overtones shape sound quality in various instruments.

  • 01:40:00 - 01:52:14

    Complicated aspects like beats in wave frequency, overtone hierarchies, and their mathematical relations are detailed, enhancing understanding of sound waves and acoustics. Discussion on frequency calculation methods and practical implications prepares viewers to tackle advanced acoustic engineering problems and understand auditory phenomena in detail.

Show more

Mind Map

Video Q&A

  • What are the types of waves discussed in the lecture?

    The lecture discusses progressive waves, standing waves, string waves, transverse waves, and longitudinal waves.

  • What is the relationship between frequency, wavelength, and velocity for waves?

    Velocity is directly proportional to wavelength, and frequency is inversely proportional to time period. Frequency depends on the source and wavelength depends on the medium.

  • What are some practical applications of wave concepts mentioned?

    Practical applications include musical instruments like drums, string instruments, and pipe instruments, illustrating how waves function in sound production.

  • What is the difference between mechanical and non-mechanical waves?

    Mechanical waves require a medium to travel, like sound waves, whereas non-mechanical waves do not require a medium, like electromagnetic waves.

  • How do waves reflect and transmit between mediums?

    Waves can reflect and transmit when transitioning between rarer and denser mediums. Their behavior is subject to phase shifts and changes in amplitude.

  • What are standing waves and how are they formed?

    Standing waves are waves that remain in a constant position, formed by the interference of two waves traveling in opposite directions with the same frequency and amplitude.

  • How is the velocity of waves in a string determined?

    The velocity of waves in a string is determined by the square root of the tension divided by the mass per unit length of the string.

  • What are some key points for understanding wave terminology?

    Key points include understanding terms like wavelength, amplitude, time period, frequency, and velocity in relation to waves.

  • What is the significance of nodes and anti-nodes in standing waves?

    Nodes are points of zero amplitude, while antinodes are points of maximum amplitude in standing waves. They determine the wave pattern and resonance.

  • How does the frequency of waves affect musical instruments?

    The frequency affects the pitch of sounds produced by musical instruments, influencing factors like harmonics and overtone properties.

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  • 00:00:00
    hi hello and welcome back
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    toy
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    channel phys the one shot with me your
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    shy M you people know when Shi mom is
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    we will be growing we will be growing
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    together okay so thanks for being with
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    me for this entire 14 chapters 14
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    chapter really LED it and
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    now in the topics okay
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    easemon is more than
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    enough okay so waves wave types wave
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    terminologies Progressive waves standing
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    waves string waves okay reflection and
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    transmission nodes anti noes
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    fixed
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    description one dimensional wave one
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    dimension so string waves are one
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    radi now let's go for the next part of
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    medium
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    sural waves possible longitudinal waves
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    important
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    terms okay now let's move for the next
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    category which is
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    terminology so illation
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    waves magnetic waves so these are very
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    very important basic
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    topics first one is
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    wavelength
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    maximum velocity may be maximum velocity
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    so
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    next
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    period time period okay so now the next
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    important thing is
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    velocity of
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    wave velocity
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    minimum energy will be
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    maximum potential energy will
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    betic energy will be minimum
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    BF
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    B these people are like the peak Point
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    maximum amplitude
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    pointel will be maximum and velocity
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    will be minimum correct will be minimum
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    and potential energy will be maximum in
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    potential energy will
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    be maximum and energy energy will be
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    minimum energy will be minimum energy
  • 00:42:06
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    as
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    Maxim oscillation so you can use each
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    perform okay ma'am electromagnetic
  • 00:43:11
    radiation you people have to understand
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    whatever the waves are traveling
  • 00:43:17
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    particle energy transformation so it
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    will be transfer place okay
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    transformation okay
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    and complete
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    analysis maximum
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    acceleration WhatsApp grou Instagram
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    anduse because lot of
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    effort class right so now the next most
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    important topic is that is your pro
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  • 00:44:50
    okay Progressive Progressive there is no
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    progress
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    Improvement movement
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    okay simple Y is equal a sin Omega t + 5
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    Point
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    listen
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    starting so in the starting point
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    fine
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    this is your
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    formula if you're taking a
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    okay in the expression
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    X
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    matter either function
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    okay function of
  • 00:50:31
    displacement this is your
  • 00:50:39
    displacement okay this is your major
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    important everything is fine
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    so
  • 00:50:58
    yal a sin Omega t +
  • 00:51:24
    5od
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    equation so t t
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    + tus x
  • 00:51:42
    / tus
  • 00:51:48
    X it doesn't matter
  • 00:51:54
    orus = to a sin Omega t + orus Omega x /
  • 00:52:02
    V +
  • 00:52:05
    5 yal a
  • 00:52:18
    sin so plus or minus
  • 00:52:21
    k x +
  • 00:52:24
    5
  • 00:52:26
    plus
  • 00:52:48
    orus a sin Omega T minus KX + Rus 5
  • 00:53:07
    okay this is much
  • 00:53:18
    important so equation Y is equal to Y is
  • 00:53:23
    equal to a a sin okay a sin Omega T
  • 00:53:28
    minus KX + Rus 5
  • 00:53:36
    [Music]
  • 00:53:48
    okay and string motion string
  • 00:53:51
    waves they are mechanical waves
  • 00:54:03
    [Music]
  • 00:54:12
    okay now
  • 00:54:18
    string because
  • 00:54:24
    of
  • 00:54:30
    what is the time period over here it is
  • 00:54:32
    T by 4 it is T by 2 it is 3 T by 4
  • 00:54:38
    T either way
  • 00:54:48
    Ang by 2 is
  • 00:54:51
    2 okay so angular time perod
  • 00:54:56
    that is very very important
  • 00:55:10
    and that will be T by 12 T by
  • 00:55:24
    12
  • 00:55:28
    and it Go and revise from your
  • 00:55:31
    oscillations
  • 00:55:38
    defin okay string
  • 00:55:41
    expression string W expression is
  • 00:55:44
    nothing but Y is equal to a sin Omega T
  • 00:55:49
    minus
  • 00:55:50
    KX plus or minus 5 okay so yeah m
  • 00:55:57
    here comes the explanation
  • 00:56:02
    listen angular frequency which is 2 pi f
  • 00:56:06
    t instant time K wave number 2 pi by
  • 00:56:23
    Lambda
  • 00:56:25
    is nothing but your
  • 00:56:28
    amplitude
  • 00:56:31
    ude
  • 00:56:40
    Point direction of
  • 00:56:52
    propagation simple listen so sin Omega
  • 00:56:57
    tus
  • 00:57:08
    KX so that
  • 00:57:20
    means that
  • 00:57:23
    means
  • 00:57:38
    negative for example
  • 00:57:41
    omegaus
  • 00:57:43
    KX
  • 00:57:53
    KX positive
  • 00:57:57
    xaxis okay it is traveling on the
  • 00:58:00
    positive
  • 00:58:01
    xais it is traveling on
  • 00:58:11
    thei everything is given over
  • 00:58:23
    here
  • 00:58:25
    okay so the next concept of discussion
  • 00:58:49
    is okay so
  • 00:58:52
    slope Dy by DX
  • 00:58:55
    slope so Dy by DX isal to M isal to tan
  • 00:59:01
    Theta
  • 00:59:23
    correct
  • 00:59:25
    that is- a k cos Omega t - KX
  • 00:59:31
    +
  • 00:59:35
    slope velocity
  • 00:59:38
    velocity velocity is nothing but dis
  • 00:59:53
    by
  • 01:00:19
    omoc okay so
  • 01:00:23
    everything so particle
  • 01:00:26
    velocity a Omega cos Omega T minus KX +
  • 01:00:42
    and next
  • 01:00:53
    important
  • 01:00:59
    V so what I'm doing
  • 01:01:10
    is divided by V particle velocity of the
  • 01:01:14
    particle so
  • 01:01:16
    ausus
  • 01:01:23
    a
  • 01:01:39
    v
  • 01:01:41
    v correct
  • 01:01:44
    slope so slope by velocity of the
  • 01:01:53
    particle velocity of the particle will
  • 01:01:56
    be equal to minus slope
  • 01:02:01
    into wave velocity minus slope into wave
  • 01:02:05
    velocity okay
  • 01:02:17
    because so positive negative into
  • 01:02:19
    positive negative particle velocity
  • 01:02:23
    negative of wave velocity
  • 01:02:26
    will be so into will be positive
  • 01:02:31
    paroc be same that of your wave
  • 01:02:37
    velocity this is going to be your
  • 01:02:39
    velocity expression
  • 01:02:48
    okay okay questions and now speed of a
  • 01:02:53
    string wave
  • 01:02:55
    okay so we are going to discuss speed of
  • 01:02:57
    the string wave this is very very
  • 01:02:59
    important and very easy Topic in the
  • 01:03:09
    topic a mechan and it is a one
  • 01:03:23
    dimension equal to root of T
  • 01:03:28
    / your
  • 01:03:30
    tension M unit length for example
  • 01:03:35
    density is equal to mass by volume okay
  • 01:03:39
    the
  • 01:03:47
    volume
  • 01:03:53
    okay
  • 01:03:55
    okay your M length is nothing but your
  • 01:03:59
    mass
  • 01:04:21
    L velocity of the particle is completely
  • 01:04:24
    depends on the tension of the string
  • 01:04:28
    tension of the string and dimensions of
  • 01:04:49
    the properties of the
  • 01:04:53
    medi the solid Medi
  • 01:04:58
    gasi and this is much much more
  • 01:05:00
    important
  • 01:05:02
    Point okay you should not
  • 01:05:06
    forgot now intensity of a string
  • 01:05:23
    we area into time energy into area into
  • 01:05:27
    time so
  • 01:05:46
    into which half into half into
  • 01:05:52
    new mass per unit
  • 01:05:55
    length mass per unit length V that is
  • 01:05:59
    your
  • 01:06:01
    velocity that is your wave velocity okay
  • 01:06:05
    wave
  • 01:06:08
    velocity okay
  • 01:06:19
    Omega that is your power that is going
  • 01:06:22
    to be the power
  • 01:06:32
    I'm half Mass into V into m² a² / L into
  • 01:06:48
    a you will be getting I is equal to half
  • 01:06:52
    r v the density of the string into
  • 01:06:56
    velocity of the wave Omega square into a
  • 01:07:00
    square okay in
  • 01:07:03
    the this is also important
  • 01:07:06
    one it is a much more damn important one
  • 01:07:11
    okay now the next topic of discussion is
  • 01:07:14
    reflection and transmission of
  • 01:07:19
    Fai yes
  • 01:07:22
    because light
  • 01:07:40
    change so reflection
  • 01:07:52
    transmission
  • 01:08:02
    either it can travel from RAR medium to
  • 01:08:05
    the
  • 01:08:09
    denser it can be traveling from the
  • 01:08:12
    denser to
  • 01:08:22
    R
  • 01:08:32
    solid dens medium that is your gas okay
  • 01:08:37
    dens medium
  • 01:08:49
    gasi you should not do that okay so RAR
  • 01:08:52
    and denser
  • 01:09:04
    [Music]
  • 01:09:17
    okay this is your rarer medium this is
  • 01:09:21
    your denser
  • 01:09:22
    medium this is
  • 01:09:37
    your so reflection and
  • 01:09:52
    trans
  • 01:10:16
    reflection RAR either
  • 01:10:20
    denser rarer denser okay
  • 01:10:52
    trans
  • 01:11:22
    180° shifting
  • 01:11:24
    180° shift so that means incident minus
  • 01:11:29
    transmitted
  • 01:11:46
    wave
  • 01:11:52
    18
  • 01:12:09
    [Music]
  • 01:12:14
    this is your normal reflected amplitude
  • 01:12:18
    correct reflected amplitude
  • 01:12:22
    and
  • 01:12:52
    face
  • 01:12:56
    okay these are the important points so
  • 01:12:58
    RAR toser
  • 01:13:16
    Med
  • 01:13:21
    okay okay
  • 01:13:38
    frequ that
  • 01:13:51
    means same frequency
  • 01:14:22
    waves
  • 01:14:51
    okayy will be definitely changing
  • 01:15:06
    [Music]
  • 01:15:08
    because okay so theud we can also
  • 01:15:11
    identify okay fine so energy is also
  • 01:15:14
    getting
  • 01:15:16
    reduced okay so now the next most most
  • 01:15:20
    important thing of discussion is
  • 01:15:22
    standing
  • 01:15:23
    Wes
  • 01:15:30
    standing same
  • 01:15:33
    frequency same
  • 01:15:37
    frequency
  • 01:15:42
    amplitude
  • 01:15:45
    velocity
  • 01:15:52
    wavelength
  • 01:15:55
    opposite to each
  • 01:16:07
    other
  • 01:16:21
    ROM OPP
  • 01:16:47
    standing wave standing wave nothing but
  • 01:16:51
    in the wave m
  • 01:17:02
    nodes will be
  • 01:17:04
    fixed nodes will be
  • 01:17:09
    fixed nod will be
  • 01:17:22
    fixed
  • 01:17:48
    resultant amplitude will be equal to 2 a
  • 01:17:52
    COS KX into sin
  • 01:17:57
    Omega Y = 2 a
  • 01:18:21
    sin = a sin Omega t + 5 correct
  • 01:18:28
    Expression 2 a COS KX
  • 01:18:43
    sin
  • 01:18:47
    stand this is your amplitude formula
  • 01:18:50
    which is 2 a COS KX 2 2 a COS KX
  • 01:18:55
    k k is nothing but your wave number okay
  • 01:18:59
    K is nothing but your wave number a 2 a
  • 01:19:03
    KX
  • 01:19:07
    okay
  • 01:19:16
    the okay so nod will be fixed
  • 01:19:21
    standing
  • 01:19:48
    amplitude ude will be
  • 01:19:50
    zero ude equal
  • 01:19:53
    zude
  • 01:19:55
    formul 2 a COS
  • 01:20:12
    kude
  • 01:20:21
    270
  • 01:20:30
    right 270 3
  • 01:20:34
    by2 5 by2 next one
  • 01:20:46
    7 by 2 next 7 Pi by 2
  • 01:20:51
    so by2 2 3 by 2 5 by2
  • 01:21:05
    7
  • 01:21:07
    for
  • 01:21:15
    okay Maxim 0
  • 01:21:20
    180 0 de 180°
  • 01:21:24
    nothing but your Z
  • 01:21:28
    180
  • 01:21:30
    2 3 Pi 2 pi 0 Pi 2 pi 3 Pi 4
  • 01:21:51
    Pi everything is for Value not for
  • 01:21:56
    Value done
  • 01:22:00
    so distance
  • 01:22:03
    between node and
  • 01:22:21
    an
  • 01:22:31
    l
  • 01:22:48
    l which is very simple and very
  • 01:22:51
    important organ
  • 01:22:54
    okay
  • 01:22:58
    so to
  • 01:23:02
    an which is your Pi by 2 okay Pi by two
  • 01:23:08
    so now we are going to discuss a very
  • 01:23:11
    important topic
  • 01:23:13
    now
  • 01:23:17
    stand now we are going to talk about
  • 01:23:19
    practical
  • 01:23:21
    application a practical application
  • 01:23:24
    practical application
  • 01:23:26
    because
  • 01:23:28
    instruments okay
  • 01:23:40
    drums string
  • 01:23:42
    instruments pip
  • 01:23:45
    instrument
  • 01:23:47
    percussion instrument okay percussion
  • 01:23:50
    instrument percussion instrument
  • 01:23:53
    okay so string
  • 01:23:56
    [Music]
  • 01:23:58
    instrument P
  • 01:24:19
    instrumented pipe open Oran pipe it is
  • 01:24:22
    based on
  • 01:24:28
    pip one closed both ends
  • 01:24:34
    closed okay we are going to discuss all
  • 01:24:38
    these things okay so we are going to
  • 01:24:40
    discuss all these things
  • 01:24:48
    now first one is fundamental frequency
  • 01:24:51
    frequency
  • 01:24:59
    that
  • 01:25:11
    means okay
  • 01:25:14
    so minue of a frequency the minimum
  • 01:25:18
    value of a vibration the lowest possible
  • 01:25:44
    over
  • 01:25:51
    third the most important
  • 01:26:21
    point
  • 01:26:22
    you people are watching session right so
  • 01:26:45
    now string fixed at one end string fixed
  • 01:26:49
    at one end close to
  • 01:26:57
    Clos okay
  • 01:27:01
    closed
  • 01:27:21
    fix
  • 01:27:28
    be careful listen carefully so now
  • 01:27:48
    closed
  • 01:27:51
    so
  • 01:28:14
    lamb so frequency V by Lambda equal to
  • 01:28:19
    frequency velocity it's wave velocity
  • 01:28:41
    L will be equal to Lambda by 4 L will be
  • 01:28:46
    equal Lambda by
  • 01:28:49
    4
  • 01:28:51
    lamb
  • 01:28:53
    so which will be Lambda isal
  • 01:28:56
    4 Lambda equal 4
  • 01:29:00
    L so V / 4 L isal to F so this is your
  • 01:29:06
    fundamental
  • 01:29:14
    frequency
  • 01:29:19
    so fix
  • 01:29:23
    fundamental formula
  • 01:29:50
    frequency so
  • 01:29:59
    L Gap Lambda by 4 Lambda by 2 + Lambda
  • 01:30:04
    by 4 is equal to length total length L
  • 01:30:10
    right
  • 01:30:16
    L Lambda isal 4 L / 3
  • 01:30:25
    V
  • 01:30:37
    4 times of your fundamental frequency so
  • 01:30:41
    three times of your fundamental
  • 01:30:46
    frequency and in the three times of
  • 01:30:48
    fundamental
  • 01:30:50
    frequency
  • 01:30:51
    [Music]
  • 01:31:09
    socon so this is how you have to
  • 01:31:14
    study this is how you have to learn so
  • 01:31:20
    now distance Lambda by 2 Lambda by 2
  • 01:31:26
    Lambda by 4 Lambda by 2 + Lambda by 2 +
  • 01:31:30
    Lambda by 4 isal to total length
  • 01:31:34
    L that will be 5 Lambda ID by
  • 01:31:39
    4al so frequency will be equal to 5 into
  • 01:31:45
    5
  • 01:31:45
    into V /
  • 01:31:50
    4
  • 01:31:53
    harmonics fifth harmonic five times of
  • 01:31:57
    your fundamental frequency for
  • 01:32:01
    example fundamental frequency is equal
  • 01:32:03
    to 100 so frequency
  • 01:32:14
    3C times of fundamental frequency third
  • 01:32:20
    Harmon this is your third
  • 01:32:23
    harmonic so this is your third
  • 01:32:26
    harmonic okay so
  • 01:32:41
    over that is
  • 01:32:44
    your that
  • 01:32:50
    means
  • 01:32:54
    people can memorize okay you people can
  • 01:32:57
    memorize so
  • 01:33:14
    fundamental second overtone fifth
  • 01:33:17
    harmonic second over fifth harmonic
  • 01:33:21
    second overtone fifth harmonic way fixed
  • 01:33:26
    at one end okay
  • 01:33:42
    so so follow these
  • 01:33:45
    formulas follow these formulas okay in
  • 01:33:49
    the formula follow
  • 01:33:52
    that is more than enough
  • 01:33:56
    okay
  • 01:34:06
    frequency
  • 01:34:08
    frequency 2 nus1 into V /
  • 01:34:12
    4 overtone second
  • 01:34:19
    overtone 2
  • 01:34:36
    okay okay so what you people have to
  • 01:34:50
    do
  • 01:34:52
    fine so now the next criteria is both
  • 01:35:00
    fixed this is your
  • 01:35:05
    open this is your closed T
  • 01:35:08
    pipe open Organ
  • 01:35:13
    Pipe Organ Pipe
  • 01:35:17
    okay
  • 01:35:20
    frequency
  • 01:35:31
    2
  • 01:35:44
    F asking for n mode of
  • 01:35:47
    frequency you have to write nid NV
  • 01:35:50
    divided by 2
  • 01:35:52
    okay
  • 01:35:59
    so
  • 01:36:06
    2
  • 01:36:07
    2 okay so the class sit for half an hour
  • 01:36:12
    and prepare your formula sheet and
  • 01:36:14
    prepare your
  • 01:36:19
    formul it won't be EAS
  • 01:36:22
    it won't be
  • 01:36:37
    easier okay so these are very very
  • 01:36:39
    important
  • 01:36:49
    topics fine so now the next topic of
  • 01:36:52
    discussion is liquid column experiment
  • 01:36:55
    and end correction okay end
  • 01:37:07
    correction but
  • 01:37:15
    your
  • 01:37:20
    okay
  • 01:37:34
    waves will be traveling
  • 01:37:47
    [Music]
  • 01:37:50
    okay
  • 01:38:20
    okay
  • 01:38:43
    will be equal velocity will be equal to
  • 01:38:46
    2 into frequency into L2 minus L1
  • 01:38:49
    negative so
  • 01:38:59
    and harmonics third order harmonics yes
  • 01:39:02
    or no this is your third order harmonics
  • 01:39:05
    right fundamental fundamental first
  • 01:39:08
    order harmonic
  • 01:39:18
    fundamental very simple thec
  • 01:39:21
    V by FAL 2
  • 01:39:25
    into that is your wavelength that is
  • 01:39:28
    your wavelength
  • 01:39:37
    so and now the next topic of discussion
  • 01:39:40
    is that is your in correction so
  • 01:39:44
    discussion end
  • 01:39:48
    correction in the end correction
  • 01:40:17
    [Music]
  • 01:40:19
    listen
  • 01:40:45
    so then only you will be getting
  • 01:40:46
    original
  • 01:40:49
    wavelength open organ
  • 01:40:53
    this
  • 01:40:55
    is effective length will be equal to l+
  • 01:40:59
    2 e
  • 01:41:02
    ection 0.6 into r r radius of your tum
  • 01:41:07
    or glass radius of your Tumbl or glass
  • 01:41:10
    okay
  • 01:41:17
    so L plus e l Plus e l plus e
  • 01:41:24
    okay open or both strings are fixed both
  • 01:41:28
    fixed
  • 01:41:29
    ends one
  • 01:41:32
    fixed one end fixed okay this is one end
  • 01:41:37
    fixed okay so now the very very very
  • 01:41:41
    very difficult
  • 01:41:47
    [Music]
  • 01:41:49
    topic
  • 01:41:52
    so it is very
  • 01:42:13
    easy but your frequency number of beats
  • 01:42:17
    per second number of cycles per second
  • 01:42:19
    number of Revolution per second number
  • 01:42:22
    of beats per second
  • 01:42:25
    okay different waves different waves
  • 01:42:40
    standing
  • 01:42:44
    no 76 okay different
  • 01:42:48
    different different different
  • 01:43:12
    for
  • 01:43:15
    example 76 beats 76 beats 700 Beats
  • 01:43:30
    6 beats per second anything per second
  • 01:43:33
    that is our
  • 01:43:35
    frequency okay
  • 01:43:38
    so
  • 01:43:40
    frequencies
  • 01:43:42
    frequencies six times
  • 01:43:49
    six or no so you will be getting six
  • 01:43:52
    Maximas and six
  • 01:43:55
    minimas in the six
  • 01:44:12
    maximum okay so this is Beats these are
  • 01:44:16
    Beats beats it's nothing but higher
  • 01:44:19
    frequency minus the frequency the
  • 01:44:49
    mod
  • 01:45:06
    one by beats reciprocal of Beats okay
  • 01:45:10
    1id fub1 minus
  • 01:45:19
    fub1
  • 01:45:38
    the
  • 01:45:41
    one okay everything should be done by
  • 01:45:44
    this time okay so now let's go to the
  • 01:45:49
    numerical parts
  • 01:45:51
    PQ start okay let's start the pyq
  • 01:45:55
    because we are done with your
  • 01:46:03
    waves so first
  • 01:46:08
    P22 so which is if the initial tension
  • 01:46:11
    of a of a stretched wire is
  • 01:46:19
    doubled
  • 01:46:23
    then the ratio of the initial and final
  • 01:46:25
    speed of a transverse wav
  • 01:46:30
    transvers of
  • 01:46:41
    Str we know velocity of a string equal
  • 01:46:44
    to root of tension ided by new that
  • 01:46:47
    means new is constant so I can say V
  • 01:46:50
    initial is directly proportional to root
  • 01:46:52
    of intention initial right other way V
  • 01:46:55
    final is directly proportional to 2 * of
  • 01:46:59
    tension
  • 01:47:07
    initi so V initial by V final is equal
  • 01:47:10
    to root of VI / root of 2 I so canel so
  • 01:47:17
    that means 1 /
  • 01:47:19
    byun2 so 1 is to < tk2 answer so the
  • 01:47:23
    answer is going to be option D so the
  • 01:47:25
    answer is going to be option D
  • 01:47:36
    15 they asking more frequently okay so
  • 01:47:43
    now a wave traveling in positive X
  • 01:47:47
    Direction so positive X
  • 01:47:49
    Direction
  • 01:48:16
    y direction as one
  • 01:48:19
    me they have given X is equal to 1 M
  • 01:48:23
    okay displacement is equal to 1
  • 01:48:26
    M wavelength is given
  • 01:48:30
    by
  • 01:48:35
    frequency frequency is given as
  • 01:48:40
    [Music]
  • 01:48:43
    1 so we people know a sin Omega T minus
  • 01:48:49
    KX
  • 01:48:52
    y equal so 1 me that is your amplitude
  • 01:48:57
    that is your amplitude so AAL 1
  • 01:49:00
    me
  • 01:49:03
    SOA is but 2 f
  • 01:49:11
    f
  • 01:49:14
    2us
  • 01:49:15
    Lambda 2 soal 2 by Lambda which is 2 Pi
  • 01:49:22
    / 2 pi cancel 1 x so the perfect answer
  • 01:49:28
    is option b so the perfect answer is
  • 01:49:31
    option b
  • 01:49:34
    okay we can identify your answers and
  • 01:49:37
    now the next question of discussion is
  • 01:49:41
    all India premedical test
  • 01:49:46
    1998 a standing wave having two nodes
  • 01:49:49
    and and two three nodes and two anti
  • 01:50:07
    noes
  • 01:50:13
    formed then the wavelength is silly
  • 01:50:17
    one total distance
  • 01:50:25
    toal which is but
  • 01:50:35
    the wavelength very
  • 01:50:38
    simple very simple very very
  • 01:50:41
    simple okay so this is how you have to
  • 01:50:49
    anal
  • 01:50:54
    okay so this is your homework
  • 01:51:04
    question this is your homework
  • 01:51:07
    question homor
  • 01:51:18
    okay
  • 01:51:20
    [Music]
  • 01:51:35
    so this is very very important okay and
  • 01:51:39
    finally thank you so much for your time
  • 01:51:41
    and patience defin
  • 01:51:48
    happy with us be with me supp energy and
  • 01:51:54
    give your support definit I will give it
  • 01:51:56
    triple the times five times greater
  • 01:51:59
    greater greater okay infinity
  • 01:52:02
    times so thank you so much for the
  • 01:52:06
    day until then it's me or shy ma'am you
  • 01:52:09
    people know when shy m'am is here no
  • 01:52:11
    fear right see you everyone
Tags
  • waves
  • physics
  • mechanical waves
  • standing waves
  • wave types
  • frequency
  • amplitude
  • wave velocity
  • reflection
  • transmission