10/16/2015
1
Clouds
What are clouds
?
A cloud is a large collection of very tiny droplets of water or
ice crystals. The droplets are so small and light that they can
float in the air.
How are clouds formed?
All air contains water, but near the ground it is usually in the
form of an invisible gas called water vapor.
When
warm air rises, it expands and cools.
Cool
air can't hold as much water vapor as warm air, so some of
the vapor condenses onto tiny pieces of dust that are floating in
the air and forms a tiny droplet around each dust particle.
When
billions of these droplets come together they become a
visible cloud.
10/16/2015
2
Why are clouds white?
Since light travels as waves of different lengths, each color
has its very own unique wavelength.
Clouds
are white because their water droplets or ice crystals
are large enough to scatter the light of the seven wavelengths
(red, orange, yellow, green, blue, indigo, and violet), which
combine to produce white light.
Why do clouds turn gray?
Clouds are made up of tiny water droplets or ice crystals,
usually a mixture of both.
The
water and ice scatter all light, making clouds appear white.
If
the clouds get thick enough or high enough all the light
above does not make it through, hence the gray or dark look.
Also
, if there are lots of other clouds around, their shadow
can add to the gray or multicolored gray appearance.
10/16/20151CloudsWhat are clouds?A cloud is a large collection of very tiny droplets of water orice crystals. The droplets are so small and light that they canfloat in the air.How are clouds formed?All air contains water, but near the ground it is usually in theform of an invisible gas called water vapor.Whenwarm air rises, it expands and cools.Coolair can't hold as much water vapor as warm air, so some ofthe vapor condenses onto tiny pieces of dust that are floating inthe air and forms a tiny droplet around each dust particle.Whenbillions of these droplets come together they become avisible cloud.10/16/20152Why are clouds white?Since light travels as waves of different lengths, each colorhas its very own unique wavelength.Cloudsare white because their water droplets or ice crystalsare large enough to scatter the light of the seven wavelengths(red, orange, yellow, green, blue, indigo, and violet), whichcombine to produce white light.Why do clouds turn gray?Clouds are made up of tiny water droplets or ice crystals,usually a mixture of both.Thewater and ice scatter all light, making clouds appear white.Ifthe clouds get thick enough or high enough all the lightabove does not make it through, hence the gray or dark look.Also, if there are lots of other clouds around, their shadowcan add to the gray or multicolored gray appearance.
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