Skip to ContentGo to accessibility pageKeyboard shortcuts menu
OpenStax Logo
Physics

Section Summary

PhysicsSection Summary

13.1 Types of Waves

  • A wave is a disturbance that moves from the point of creation and carries energy but not mass.
  • Mechanical waves must travel through a medium.
  • Sound waves, water waves, and earthquake waves are all examples of mechanical waves.
  • Light is not a mechanical wave since it can travel through a vacuum.
  • A periodic wave is a wave that repeats for several cycles, whereas a pulse wave has only one crest or a few crests and is associated with a sudden disturbance.
  • Periodic waves are associated with simple harmonic motion.
  • A transverse wave has a disturbance perpendicular to its direction of propagation, whereas a longitudinal wave has a disturbance parallel to its direction of propagation.

13.2 Wave Properties: Speed, Amplitude, Frequency, and Period

  • A wave is a disturbance that moves from the point of creation at a wave velocity vw.
  • A wave has a wavelength λ λ, which is the distance between adjacent identical parts of the wave.
  • The wave velocity and the wavelength are related to the wave’s frequency and period by v w = λ T v w = λ T or v w =fλ . v w =fλ .
  • The time for one complete wave cycle is the period T.
  • The number of waves per unit time is the frequency ƒ.
  • The wave frequency and the period are inversely related to one another.

13.3 Wave Interaction: Superposition and Interference

  • Superposition is the combination of two waves at the same location.
  • Constructive interference occurs when two identical waves are superimposed exactly in phase.
  • Destructive interference occurs when two identical waves are superimposed exactly out of phase.
  • A standing wave is a wave produced by the superposition of two waves. It varies in amplitude but does not propagate.
  • The nodes are the points where there is no motion in standing waves.
  • An antinode is the location of maximum amplitude of a standing wave.
  • Reflection causes a wave to change direction.
  • Inversion occurs when a wave reflects from a fixed end.
  • Refraction causes a wave’s path to bend and occurs when a wave passes from one medium into another medium with a different density.
Order a print copy

As an Amazon Associate we earn from qualifying purchases.

Citation/Attribution

This book may not be used in the training of large language models or otherwise be ingested into large language models or generative AI offerings without OpenStax's permission.

Want to cite, share, or modify this book? This book uses the Creative Commons Attribution License and you must attribute Texas Education Agency (TEA). The original material is available at: https://www.texasgateway.org/book/tea-physics . Changes were made to the original material, including updates to art, structure, and other content updates.

Attribution information
  • If you are redistributing all or part of this book in a print format, then you must include on every physical page the following attribution:
    Access for free at https://openstax.org/books/physics/pages/1-introduction
  • If you are redistributing all or part of this book in a digital format, then you must include on every digital page view the following attribution:
    Access for free at https://openstax.org/books/physics/pages/1-introduction
Citation information

© Jan 19, 2024 Texas Education Agency (TEA). The OpenStax name, OpenStax logo, OpenStax book covers, OpenStax CNX name, and OpenStax CNX logo are not subject to the Creative Commons license and may not be reproduced without the prior and express written consent of Rice University.