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Unit: Oscillations and mechanical waves

In these videos and articles you'll learn the definition of a wave and the difference between transverse and longitudinal waves. You'll also learn the definition of the basic terms used to characterize waves; amplitude, period, frequency, and wavelength.
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.
In these videos and articles you'll learn how standing waves are produced and how to determine the wavelength and frequency of the different harmonics of standing waves produced in an open open tube or an open closed tube.

About this unit

This unit is part of the Physics library. Browse videos, articles, and exercises by topic.