Roger Keevy's Profile

categorize waves

three notable
categories: transverse waves, longitudinal waves, and
surface waves.

particles of the medium move in a direction
perpendicular to the direction which the wave moves

particles of the medium move in a direction
parallel to the direction which the wave moves

longit

sound wave

classic example of a

sound wave

particles of air vibrate back and forth in the same
direction and the opposite direction of energy transport.

of particle
#1 with its neighbor serves to restore particle #1 to its
original position and displace particle #2 in a forwards
direction. This back and forth motion of particles in the
direction of energy transport creates regions within the
medium where the particles are pressed together and other
regions where the particles are spread apart.

Waves traveling through a solid medium can
be either transverse waves or longitudinal waves.

Yet waves
traveling through the bulk of a fluid (such as a liquid or a
gas) are always longitudinal waves. Transverse waves require
a relatively rigid medium in order to transmit their energy.

exert a
pull on its nearest neighbor

neither longitudinal nor
transverse

particles of the medium undergo a circular
motion

it is only the particles at the surface of the medium
which undergo the circular motion. The moti

on of particles
tend to decrease as one proceeds further from the
surface.

a medium has a
source

initial
displacement of one of the particles

Another way to categorize waves is on the basis of their
ability or inability to transmit energy through a vacuum
(i.e., empty space). Categorizing waves on this basis leads
to two notable categories: electromagnetic waves and
mechanical waves.

apable of transmitting its energy through a
vacuum

produced by the vibration of charged particles

All light waves are examples of
electromagnetic waves.

not capable of transmitting its energy through
a vacuum

require a medium in order to
transport their energy from one location to another.

Sound waves are
incapable of traveling through a vacuum. Slinky waves, water
waves, stadium waves, and jump
rope waves are other examples of mechanical waves; each
requires some medium in order to exist.

particle is displaced

A
pulse is a single
disturbance moving through a medium

repeating and periodic
disturbance which moves through a medium from one location
to another is referred to as a
wave.

A
medium is a substance or
material which carries the wave.

In a similar manner, a wave
medium is the substance which carries a wave (or
disturbance) from one location to another. The wave medium
is not the wave and it doesn't make the wave; it merely
carries or transports the wave from its source to other
locations.

When a wave is present in a medium

the individual
particles of the medium are only temporarily displaced from
their rest position.

There is always a force acting upon the
particles which restores them to their original position.

The particles of the medium (water molecules, slinky coils,
stadium fans) simply vibrate about a fixed position as the
pattern of the disturbance moves from one location to
another location.

To fully understand the nature of a wave, it is important
to consider the medium as a collection of interacting
particles.

This characteristic of a wave as an energy
transport phenomenon distinguishes waves from other types of
phenomenon.

Consider

In a wave phenomenon, energy can
move from one location to another, yet the particles of
matter in the medium return to their fixed position. A wave
transports its energy without transporting matter.

the disturbance travels
through the medium. The medium can be pictured as a series
of particles connected by springs. As one particle moves,
the spring connecting it to the next particle begins to
stretch and apply a force to its adjacent neighbor. As this
neighbor begins to move, the spring attaching this neighbor
to its neighbor begins to stretch and apply a force on its
adjacent neighbor.

In
a water wave, energy is transported without the transport of
water.

Waves involve the
transport of energy without the transport of matter.

In conclusion, a wave can be described as a disturbance
which travels through a medium, transporting energy from one
location (its source) to another location without
transporting matter. Each individual particle of the medium
is temporarily displaced and then returns to its original
equilibrium positioned.

Waves are said to be an
energy transport
phenomenon