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Main content
In this lesson, you'll learn the definition of a wave and the difference between transverse and longitudinal waves.
In this lesson, we'll discuss how waves can overlap to produce constructive or destructive interference.
In this lesson, we'll discuss how and why standing waves occur, and well as how to determine the wavelength and frequency for a standing wave.
In these videos and articles you'll see visualizations of the propagation of sound waves, along with a visual definition of a sound wave's amplitude, period, frequency, and wavelength. You'll also learn how the speed of sound depends on the different characteristics of the medium. It will be shown how Mach numbers characterize faster than sound travel and their relationship to sonic booms. Also, you'll learn about the decibel scale, why sounds get softer, and how ultrasound medical imaging works.
In these videos and articles you'll learn how the Doppler effect causes a change in the measured frequency of a moving source of sound or moving sound detector. You'll also learn how to calculate the observed frequency using the formula for the Doppler effect when dealing with either a moving source of sound or a moving sound detector.

About this unit

Waves are responsible for basically every form of communication we use. Whether you're talking out loud or texting on your phone, there's going to be a wave transmitting information. Learn the fundamentals of waves and sound in this unit.