No one likes clouds when they bring rain, but what if you could
make you own?
Remember to ask your parents for help with matches.
You need:
- Plastic water bottle with a sports cap
- Warm water
- Matches
This video shows you what to do:
How to:
- Pour a little bit of water into the plastic bottle.
- Put the cap back on, but leave it open.
- Light the match, then blow it out so it smokes.
- Suck the smoke into the bottle by squeezing the bottle gently a
few times.
- Close the cap.
- Squeeze the bottle and then release it.
- Repeat step 6 several times.
What do you see?
When you squeeze the bottle, there is no cloud. When you release
the bottle, a cloud appears! You've just made your own
cloud.
How do real clouds form?
Clouds require three things to form:
- Water molecules
- Cloud condensation nuclei - dust or air pollution
- Temperature or pressure changes
Water molecules are in the air all around us, even though we
can't normally see them. Normally, these water molecules bounce
around.
Real clouds form when warm air rises in the atmosphere and cools
down. Cloud condensation nuclei, such as small
particles of dust and pollution, enable water molecules to stick
together and stop bouncing around. The water molecules condense
around the nuclei to form clouds. Clouds are just groups of tiny
water droplets that stick together around cloud condensation nuclei
when temperatures are low.
How does the cloud in a bottle form?
Clouds are more likely to form when it's cold. When you squeeze
the bottle, the pressure increases. This causes the temperature
inside the bottle to rise. When you release the bottle, the
pressure decreases. This causes the temperature inside the bottle
to fall and the water molecules to condense. The smoke particles
act as cloud condensation nuclei, allowing the water molecules to
condense and stick together around the smoke. There you go - a
cloud in a bottle!
If you use water of different temperatures, does that affect the
cloud in your bottle? What if you used something other than smoke
for cloud condensation nuclei? How would that affect cloud
formation?
If you like this, have a look at Weather Labs
to find out all about weather and test the weather forecast!