Answer 1:
1. Ocean waves are a form of energy that can be
described with physics. They have a velocity and
they do have friction from the air above them and
the water around them. When the waves enter
shallow water, they spill over in part due to
friction from the ocean bottom. There are other
waves in physics like sound waves and electrical
waves.
2. I would label the crest (top),
the trough (bottom), and the distance between the
two (amplitude). I would also label the distance
between two tops of the wave.
3. Waves are
created by the wind from storms. We have storms
in the winter because the northern half of the
earth is tilted away from the sun during that part
of the year. In the summer, the southern half of
the earth is tilted away from the earth and there
are storms down there. Often times, the waves
from the southern half travel all the way up here.
So the main difference with each season is where
the waves come from. Because we are so far away
from the southern half of the earth, the waves
from there experience a lot of friction and are
smaller.
4. I think a poster with labels
would be good. Maybe you could blow air on a
container of water and make your own waves. Or
use a piece of string to make a wave.
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Answer 2:
1.The concept of "waves" appear in many different
branches of physics. Ocean waves are an example
of "mechanical" waves, or waves that propagate
(travel) in an elastic (deformable) media. In
this case, the media is the water.
There
are two types of mechanical waves:
Transverse waves are waves where the
motion of the medium conveying the waves is
perpendicular to the direction the wave is
traveling. Imagine tying one of a rope to a fixed
object and then stretching the rope out. If you
then start "snapping" the rope, you can make a
wave on the rope. What you see, is that the wave
propages down the rope, while the parts of the
rope are just moving up and down, or perpendicular
to the rope.
Longitudinal waves are waves
where the motion of the medium conveying the waves
is parallel (back and forth) to the direction the
wave is traveling. If instead of a rope, one
extended out a giant spring (or slinky!) that was
fixed on one end, we can see a different behavior.
If we now start pushing and pulling the spring in
the same direction it is extended, you can see a
"pulse" type wave moving down the spring, and that
is a longitudinal wave.
Ocean waves are
actually a combination of these different types of
waves. If you're on a boat, you mostly would
notice the up and down motion of the transverse
part of the wave. However, instead of going just
up and down, there is usually more of an
elliptical motion to the "rocking" which is brough
on by the longitudinal contribution that pushes
you back and forth.
For transverse waves,
we think about them as oscillations around a
median value. The maximum displacement of a wave
from the median value is called the amplitude.
The distance between identical points on the wave
is called the wavelength. The other key feature
of a wave is it's period. The period of the wave
is the time required for the wave to travel a
distance of 1 wavelength, and hence is a measure
of the velocity the wave is traveling at. Also,
the highest points of the wave are called the
"peaks" and the lowest parts of the wave are
called the "troughs."
3. Wind is actually
the most common cause of waves. Basically, the
wind applies a shearing force across the surface
of the water that gives you waves (the same thing
if you blow across the top of water and see
ripples form. Waves can also be formed for
geological sources such as offshore earthquakes
and volcanic eruptions. Other factors such as
underwater currents can also cause waves.
A
related phenomeon are the tides, which is the
rising and falling of ocean levels. These are
primarily determined by the position of the moon
and the sun (note that the sun's contribution is
about half that of the moon because it is so far
away from the earth!). It might be possible that
since the earth's orbit is elliptical, the
contribution to the tides from the sun will vary
with the seasons, but I am not sure how big of an
effect that is. In situations where the
contribution of the sun and moon to the tides work
together and are additive, you get "spring tides,"
although, I do not believe that they are actually
correlated with happening in the spring!
4.
I do not have any particular suggestions other
than what I have written in parts 1-3, but
hopefully that will get you started and on your
way. In addition to the "basics" of waves, I
would research the different causes of waves to
discuss in more detail how waves form and travel.
Good luck!
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Answer 3:
The kinds of properties of waves a physicist might
think about are the amplitude (height) of the
wave, the speed at which it moves, the
distance between one wave and the next, and
whether any of the properties change as the
wave travels.
A physicist would like to
understand what causes an ocean wave and how
conditions of the atmosphere, the water, and the
ocean floor cause the properties of a wave to
change. Some examples: How does changing the
temperature of the ocean, change how waves
move? How does wind speed effect waves? Does it
matter whether the ocean is deep or shallow?
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