Vijay Luxmi Askiitiansexpert
Last Activity: 14 Years ago
Dear Kailly,
Explanation for wave motion:
The easiest wave to visualize is a water wave. When a pebble is dropped in a calm pool of water, ripples travel out from the point where the pebble enters the water. The disturbance travels out from the center of the pattern, but the water does not travel with the wave. Mechanical waves—such as water waves, waves on a rope, waves in a spring, and sound waves—have two general characteristics:
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A disturbance is in some identifiable medium.
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Energy is transmitted from place to place, but the medium does not travel between two places.
For the sake of simplicity, idealized one-dimensional waves on a rope and two-dimensional water surface waves with no friction-like forces provide the wave model. For ease of analysis, a pulse that is a single short wave will be used to illustrate wave characteristics that also hold true for more complex waves.
On the left side of Figure , a pulse travels on a string. As the pulse passes point P on the string, the point moves up and then back to the equilibrium position. Each segment of the rope moves only perpendicular to the motion of the wave. This type of traveling wave is called a transverse wave.
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Transverse (a) and longitudinal (b) waves.
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The right side of Figure shows the pulse propagated along a stretched spring. In this case, the individual points along the medium (the spring) travel back and forth parallel to the motion of the pulse. This type of traveling wave is called a longitudinal wave. Sound waves are longitudinal waves.