|How do rainbows happen?
|Question Date: 2018-10-12|
Rainbows like the ones we see during or after rain
come from white light of the sun interacting
with tiny droplets of water in the air.
During or after rain, there is a much higher
number of small water droplets light enough to
float in the air. The water droplets can
reflect light, bend light, or disperse light -
dispersing light generally means splitting
light into its different colors. In the case
of sunlight, because it is mostly white light, its
dispersion by the water droplets can result in the
full spectrum of visible light, which we
perceive as a rainbow. Because of the way
light works, we as observers can only see rainbows
at certain angles relative to the source of the
light. The required angle explains why, when
we use a hose with fine spray of water on a sunny
day, we can see small rainbows only from certain
directions and not others.
Side note: We see distinct colors in a rainbow
because our eyes are not sensitive enough to see
every wavelength of the visible light spectrum. In
reality, every wavelength of the visible
spectrum is in a rainbow.
Rainbows happen when sunlight shines through
rain drops. Sunlight is white, but white
light contains all of the other colors. When white
light shines into a raindrop, the light bends
and is reflected off the inside of the drop and
back out to the viewer. When this happens,
each component color bends by a different amount,
so we see them separately as a rainbow.
Rainbows are caused by sunlight reflecting off
of the back sides of rain drops back at the
viewer, but because different colors of light
are bent different amounts as they enter and leave
water, they are smeared out through the
electromagnetic spectrum, creating bands of
different colors as light from slightly
different angles reaches your eye.
White light has all the colors of the
rainbow. This seems a bit strange, because
you'd get paint that was very dark if you mixed
all the colors together.
White light from the sun can bend when it
hits water droplets in the atmosphere.
Different colors of light have longer and shorter
wavelengths, and they bend more or less, so the
light from the sun is separated into all the
colors of the rainbow. You can see, from the
rainbow, which colors of light have wavelengths
that are the move similar, because those colors
are next to each other in the rainbow.
Here's part of what Wikipedia says about rainbows:
read about rainbow
A rainbow is a meteorological phenomenon that is
caused by reflection, refraction and dispersion
of light in water droplets resulting in a
spectrum of light appearing in the sky. It takes
the form of a multicolored circular arc. Rainbows
caused by sunlight always appear in the section of
sky directly opposite the sun.
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