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| Types of Waves |
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| These are waves which require a material medium for their propagation and can be described using Newton's laws of motion. |
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| Examples: water waves, sound waves, seismic waves, and shock waves. |
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| Mechanical wave motion can be defined as the propagation of a disturbance through a material medium due to the repeated periodic motion of the particles of the medium about their mean positions, the disturbance being handed over from one particle to the next. |
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| The two properties of a medium that govern the
behavior of a mechanical wave are: |
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 a restoring force |
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 an inertial mass |
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| In the case of a water wave, gravity provides a force that tends to restore water to its equilibrium (flat) condition. Water has inertial mass. Therefore, it overshoots the equilibrium condition. The disturbance persists and the wave propagates. |
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| These are waves that can pass through vacuum in addition to passing through matter. In other words, a material medium is not necessary for their propagation. They consist of periodic variations of electric and magnetic fields at right angles to each other and also at right angles to the direction of propagation. |
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| Examples:- light waves, radio waves, micro waves, x-rays. |
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| Under certain experimental conditions, a beam of particles (for example, electrons ) can exhibit wavelike properties. Such matter waves are governed by the laws of quantum physics. The wavelength is inversely proportional to the momentum of the particles. These are also known as de Broglie waves. |
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| Only mechanical waves will be considered in the following discussions. In a wave, it is the dynamic condition that is handed over from particle to particle. According to the laws of physics, the dynamic condition is related to momentum and energy. Thus, in wave motion, matter is not propagated, but it is energy and momentum. A wave is said to be progressive if it travels onwards, with energy transference across every section of the medium. A wave is said to be a stationary or a standing wave if there is no onward movement of the wave through the medium. Hence, there is no transference of energy across any section of it. It is confined to a specific region of space by boundaries (e.g., a vibrating guitar string). The energy associated with such a wave remains within the boundaries. |
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| Waves are classified in accordance with the motion of the local part of the medium with respect to the direction of propagation. The most common types are transverse waves and longitudinal waves. Other types of waves are also frequently observed, which are usually a combination of transverse and longitudinal waves. |
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