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  • State the characteristics of a wave.
  • Calculate the velocity of wave propagation.
There is a high tidal wave of about 10 feet high in a sea. Three boats carrying three four persons each are ahead of the wave, which is coming toward them.
Waves in the ocean behave similarly to all other types of waves. (credit: Steve Jurveston, Flickr)

What do we mean when we say something is a wave? The most intuitive and easiest wave to imagine is the familiar water wave. More precisely, a wave    is a disturbance that propagates, or moves from the place it was created. For water waves, the disturbance is in the surface of the water, perhaps created by a rock thrown into a pond or by a swimmer splashing the surface repeatedly. For sound waves, the disturbance is a change in air pressure, perhaps created by the oscillating cone inside a speaker. For earthquakes, there are several types of disturbances, including disturbance of Earth’s surface and pressure disturbances under the surface. Even radio waves are most easily understood using an analogy with water waves. Visualizing water waves is useful because there is more to it than just a mental image. Water waves exhibit characteristics common to all waves, such as amplitude, period, frequency and energy. All wave characteristics can be described by a small set of underlying principles.

A wave is a disturbance that propagates, or moves from the place it was created. The simplest waves repeat themselves for several cycles and are associated with simple harmonic motion. Let us start by considering the simplified water wave in [link] . The wave is an up and down disturbance of the water surface. It causes a sea gull to move up and down in simple harmonic motion as the wave crests and troughs (peaks and valleys) pass under the bird. The time for one complete up and down motion is the wave’s period T size 12{T} {} . The wave’s frequency is f = 1 / T size 12{f=1/"T"} {} , as usual. The wave itself moves to the right in the figure. This movement of the wave is actually the disturbance moving to the right, not the water itself (or the bird would move to the right). We define wave velocity     v w size 12{v rSub { size 8{"w"} } } {} to be the speed at which the disturbance moves. Wave velocity is sometimes also called the propagation velocity or propagation speed , because the disturbance propagates from one location to another.

Misconception alert

Many people think that water waves push water from one direction to another. In fact, the particles of water tend to stay in one location, save for moving up and down due to the energy in the wave. The energy moves forward through the water, but the water stays in one place. If you feel yourself pushed in an ocean, what you feel is the energy of the wave, not a rush of water.

The figure shows an idealized ocean wave with two crests and two troughs that passes under a sea gull that bobs up and down in simple harmonic motion. The wave has a wavelength lambda which is the distance between adjacent identical parts of the wave. The height of a crest is equal to the depth of the trough that is X, therefore the total vertical distance between the top of a crest and the bottom of the trough is two-X.
An idealized ocean wave passes under a sea gull that bobs up and down in simple harmonic motion. The wave has a wavelength λ size 12{λ} {} , which is the distance between adjacent identical parts of the wave. The up and down disturbance of the surface propagates parallel to the surface at a speed v w size 12{v rSub { size 8{"W"} } } {} .

The water wave in the figure also has a length associated with it, called its wavelength     λ , the distance between adjacent identical parts of a wave. ( λ size 12{λ} {} is the distance parallel to the direction of propagation.) The speed of propagation v w size 12{v rSub { size 8{w} } } {} is the distance the wave travels in a given time, which is one wavelength in the time of one period. In equation form, that is

Questions & Answers

Calculate the work done by an 85.0-kg man who pushes a crate 4.00 m up along a ramp that makes an angle of 20.0º20.0º with the horizontal. (See [link] .) He exerts a force of 500 N on the crate parallel to the ramp and moves at a constant speed. Be certain to include the work he does on the crate an
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there is enough information to calculate an AVERAGE acceleration
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mistake, there is enough information to calculate an average velocity
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It is the opposite of kinetic friction
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static fiction is friction between two surfaces in contact an none of sliding over on another, while Kinetic friction is friction between sliding surfaces in contact.
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I don't get it,if it's static then there will be no friction.
author
It means that static friction is that friction that most be overcome before a body can move
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It is a force a body must overcome in order for the body to move.
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what is wave
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what is force
Muhammed
force is something which is responsible for the object to change its position
MINDERIUM
more technically it is the product of mass of an object and Acceleration produced in it
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energy is distributed in any medium through particles of medium.
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we have to first figure out .... wats a particle accelerator first
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The resistive force of surface.
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on both a string and peldulum?
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spring*
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Which is
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teach him SHM init
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Simple harmonic motion
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how.an.equipotential.line is two dimension and equipotential surface is three dimension ?
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definition of mass of conversion
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Force equals mass time acceleration. Weight is a force and it can replace force in the equation. The acceleration would be gravity, which is an acceleration. To change from weight to mass divide by gravity (9.8 m/s^2).
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how many subject is in physics
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the write question should be " How many Topics are in O- Level Physics, or other branches of physics.
effiom
how many topic are in physics
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Heat nd Co for a level
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yh I need someone to explain something im tryna solve . I'll send the question if u down for it
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hallow
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Practice Key Terms 4

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Source:  OpenStax, College physics. OpenStax CNX. Jul 27, 2015 Download for free at http://legacy.cnx.org/content/col11406/1.9
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