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Mechanical Waves

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In mathematics and science, a wave is a disturbance that travels through space and time, usually accompanied by the transfer of energy.mathematicssciencespace time energy

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What are mechanical waves? A mechanical wave is a disturbance in matter that carries energy from one place to another.

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3 Main Types of Mechanical Waves Transverse Longitudinal Surface

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Transverse Waves A transverse wave causes the medium to vibrate in a direction perpendicular to the direction in which the wave travels.

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Transverse Waves A transverse wave is a wave in which particles of the medium move in a direction perpendicular to the direction that the wave moves

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Shaking one end of a rope up and down creates Transverse Waves

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Human Wave is a Transverse Wave

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Direction of the Transverse Wave

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Check for understanding. Move a rope up and down and observe the waves. How does the direction of the wave compare with the direction in which the rope moves? Create a human wave like at a ball game. How does the direction of the wave compare with the direction in which the wave moves? In a transverse wave, the particle motion is perpendicular to the direction of the wave velocity. A transverse wave may be created by shaking one end of a rope up and down or side to side. One example is a ripple on a pond.

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Longitudinal Waves = A longitudinal wave is a wave in which the vibration of the medium is parallel to the direction of the wave. parallel circuit parallel port parallel planting

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Longitudinal Waves

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Check for Understanding: What are compressions and rarefactions in Longitudinal Waves? An area where the particles are spaced close together is called a compression. An area in a medium where particles are spread out is called a rarefaction.

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Surface Waves Surface waves are combinations of transverse and longitudinal waves. These waves occur at the surface between two mediums, such as water and air. Up-and-down motion combines with back-and-forth motion. The combination produces circular motion.

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Surface Waves

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Surface Wave A surface wave is a wave that travels along a surface separating two media.

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http://www.youtube.com/watch?v=7yPTa8qi5X8 A surface wave is a wave that travels along a surface separating two media, such as water and air.

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Check for Understanding Surface Waves Where do surface waves occur? at the surface between two mediums. How do surface waves move? up and down like a transverse wave on a rope, and back and forth like coils in a spring.

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Vocabulary: Properties of Mechanical Waves wavelength, The wavelength, is the distance from any point on the wave to the adjacent point(one complete wave). amplitude The amplitude of a wave is the maximum height of the wave. The amplitude does not affect the wave speed. frequency, Hz The frequency, Hz of a wave is the number of oscillations of cycles during an amount of time, usually a second. Frequency is measured in Hertz. One hertz is one cycle per second. period The period of a wave is the time it takes for the wave to travel a distance of one wavelength.

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Longitudinal Wave vs. Transverse Wave

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Summary http://www.passmyexams.co.uk/GCSE/physics /basic_waves_theory.html http://www.passmyexams.co.uk/GCSE/physics /basic_waves_theory.html

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Wave examples which illustrate the definitions http://paws.kettering.edu/~drussell/Demos/waves-intro/waves-intro.html http://paws.kettering.edu/~drussell/Demos/waves-intro/waves-intro.html Transverse Waves Longitudinal Waves Surface Waves

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A disturbance that transfers energy from place to place. A source of energy that causes a medium to vibrate. Where do waves get their energy? Transverse- human wave; shaking a rope Longitudinal- coiled spring; sound Surface- ocean wave Give examples of the 3 main types of waves. Solid Medium (e.g. land) Gas Medium (e.g. air) Liquid Medium (e.g. water) How are mechanical waves carried?