EXPERIMENTS



external image JYMmnpV9X3.gif

external image CloudsInABottle.jpg

What are clouds?
A cloud is a large collection of very tiny droplets of water or ice crystals. external image SkyCloudsBlueScatted1832-706827.jpg
The droplets are so small and light that they can float in the air.



How are clouds formed?
Cumulus Clouds
Cumulus Clouds
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.


Why are clouds white?
Clouds are white because they reflect the light of the sun. Light is made up of
colors of the rainbow and when you add them all together you get white. The
sun appears a yellow color because it sends out more yellow light than any other
color. Clouds reflect all the colors the exact same amount so they look white.


Why do clouds turn gray?
Storm Clouds
Storm Clouds
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 be
multicolored gray appearance.



Why do clouds float?
A cloud is made up of liquid water droplets. A cloud forms when air is heated by the sun.
As it rises, it slowly cools it reaches the saturation point and water condenses, forming a
cloud. As long as the cloud and the air that its made of is warmer than the outside air around it, it floats!


How do clouds move?
Clouds move with the wind. High cirrus clouds are pushed along by the jet stream,
sometimes traveling at more than 100 miles-per-hour. When clouds are part of a
thunderstorm they usually travel at 30 to 40 mph.

How is fog formed?
There are many different types of fog, but fog is mostly formed when southerly winds bring warm,
Cloud
Cloud
moist air into a region, possibly ending a cold outbreak. As the warm, moist air flows over much
colder soil or snow, dense fog often forms. Warm, moist air is cooled from below as it flows over
a colder surface. If the air is near saturation, moisture will condense out of the cooled air and
fog. With light winds, the fog near the ground can become thick and reduce visibilities to zero.




Our Experiment


CLOUD IN A BOTTLE
Cloud
Cloud

MATERIALS:


  • 2-liter clear plastic pop bottle
  • matches
  • warm water
PROCESS:
Fill the clear plastic 2-liter bottle one-third full of warm water and place the cap on. As warm water evaporates, it adds water vapor to the air inside the bottle. This is the first ingredient to make a cloud.
Squeeze and release the bottle and observe what happens. You’ll notice that nothing happens. Why? The squeeze represents the warming that occurs in the atmosphere. The release represents the cooling that occurs in the atmosphere. If the inside of the bottle becomes cover with condensation or water droplets, just shake the bottle to get rid of them.
Take the cap off the bottle. Carefully light a match and hold the match near the opening of the bottle.
aPicture_001.jpg
Then drop the match in the bottle and quickly put on the cap, trapping the smoke inside

aPicture_002.jpg
Dust, smoke or other particles in the air is the second ingredient to make a cloud.
Once again, slowly squeeze the bottle hard and release.
aPicture_003.jpgaPicture_004.jpg
What happens? A cloud appears when you release and disappears when you squeeze. The third ingredient in clouds is a drop in air pressure.
EXPLANATION:
Water vapor, water in its invisible gaseous state, can be made to condense into the form of small cloud droplets. By adding particles such as the smoke enhances the process of water condensation and by squeezing the bottle causes the air pressure to drop. This creates a cloud!