Download 12.7 Mirages, Apparent Depth, Rainbowsfill

Mirages, Rainbows, Apparent Depth, Flattened Sun
MIRAGE
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This commonly occurs on summer days, when an asphalt road that has been baking in
the sun heats the air directly above it, creating a sharp shift in air density levels near the
ground. As light passes between the different levels, it bends, creating mirages.
Normally, sunlight bouncing off an object (let's say a car) reflects in all directions. You
see the car when your eyes detect this light.
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Since the human brain perceives light moving in a straight line the image is projected as
if it were ____ the asphalt.
RAINBOWS
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To see a rainbow, there should be a little rain or moisture in the sky and the Sun
should be shining behind you.
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Refracted means the light of the sun is split up into its basic colors. Sunlight is
actually a combination of Red, Orange, Yellow, Green, Blue, Indigo, and Purple.
When a beam of sunlight comes down to Earth, the light is white. But, if the
light beam happen ___________________________________________
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The angle of incidence for each color of a rainbow is different, because
each _______ travels at a different speed when it enters the raindrop. The
light exits the raindrop in _____ colour, depending on the angle it came in,
so we see only one color coming from each raindrop. _____________
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APPARENT DEPTH
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The apparent depth of an object will look less than its real depth due to the refraction of
light.
imagine an object at the bottom of the pond emitting a beam of light straight to the centre
of your eye.
Now, _______________________________________________________________
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Remember our brain perceives light travelling in a ________________________
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shallower than the actual depth
FLATTENED SUN
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This flattening of the sun on the horizon is an example of a mirage
The optical density of air is related to temperature.______________________________
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The atmosphere, particularly in the early morning, usually has a layered structure; air
temperature changes with height.
If the sun is on, or just below the horizon, the light travels along a long path through the
atmosphere.
As the light passes through these different layers, it will _________________, flatten or distort
the sun’s disk. Light rays coming from the top of the sun bend ______ than rays coming from the
bottom, slightly squashing the sun’s circular shape.
Our human brains again perceive light in a ___________________ projecting the rays backwards
as a flat sun
SHIMMERING
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When air is hot it expands. Light will travel through hot air slightly faster than cold air.
When light changes its speed due to different air temperatures, it will refract. The result
is light bending in all of directions which change as the air moves and we see this as
shimmering.
The same effect makes stars twinkle. The light waves are being distorted