wave motion

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What’s the first thing that comes to mind when you hear the word “wave”? We often think of common forms of waves such as the waves in the ocean. But there are many kinds of waves. Waves are all around us and we encounter them everyday. There are light waves, sound waves, and many more. In this section, we are going to look at common types of waves, what parts make up those waves, and real life examples of waves.

Amplitude is a measurement from equilibrium to the crest of a wave. Equilibrium is the point half way in between a

crest and a trough in the vertical direction. We

measure to the crest instead of the trough because then the amplitude is a positive

number. Amplitude is a measure of the intensity of a

wave. The symbol for amplitude is A and it is measured in meters.

The wavelength is the length of one

complete wave, or cycle. It is measured from crest to crest or from trough to trough for transverse waves.

It is similar for longitudinal waves as well. The symbol for wavelength is the

Greek letter lambda (λ) and is measured

in meters.

Period is the time it takes to complete one full cycle of a wave. A cycle is

from rarefaction to rarefaction or from

compression to compression for

longitudinal waves. It is similar for

transverse waves as well. The

symbol for period is T and it is measured in

seconds.

Frequency is the number of cycles

that occur for every unit of time. There are two equations

for frequency. These are used to make calculations with waves. The

symbol for frequency if f and it

is measured in cycles per second.

Frequency is the inverse of period:

Frequency is equal to the velocity ofa wave divided by the wavelength:

The crest is the highest point in the vertical direction for a transverse wave.

Similarly, the trough is the lowest point in the vertical

direction.

The compression of a longitudinal wave

is the part of the wave where the

particles in a wave are most dense.

Rarefaction is the part of the wave

where the particles are least dense.

There are many types of waves. In this section,

we’re specifically going to look at transverse waves and longitudinal waves,

as well as examine a special type of wave

called a standing wave. They are examples of mechanical waves. An

important concept about wave motion is that

waves transfer energy, NOT matter.

A transverse wave is characterized by

particle motion that is perpendicular to the wave energy. It

is important to understand that an individual particles do not move from

there original position on the

horizontal axis, they merely oscillate

vertically.

Click on the picture to visit a websitethat let’s you adjust the wavelengthand amplitude of a transverse wave.

A longitudinal wave is characterized by particle motion that

is parallel to the direction of the

wave energy. Even though they are in the same direction,

it is important to note that a particle does not move with the wave, it merely

oscillates in the same direction.

Click on the picture to visit a websitethat shows animated pictures of wavemotion.

In 1940, the Tacoma Narrows Bridge collapsed…

BONUS! News Reel For the Tacoma Narrows Tragedy

Know the following concepts and how to apply them to problems for the next

exam: