- University of Virginia
- Physics Department
Evaporation and Heat Engines
A Physical Science Activity
- One Tablespoon water
- One Tablespoon rubbing alcohol
- Two clear plastic cups
- Pour the water into one cup and the rubbing alcohol into the other cup.
- Observe the two samples, and after several minutes note which liquid seems
to have evaporated faster.
- Place a few drops of water on one hand and a few drops of rubbing alcohol
on the other hand.
- Wave your two hands slowly through the air. Note any difference in how
each hand feels. Does one feel cooler than the other?
1. Which substance seems to have evaporated faster, water or alcohol? How can
2. When you waved your hands in the air, which felt cooler? Why did your hands
3. Where did the heat come from that made the liquid evaporate from your hands?
4. Explain in your own words how the Drinking Bird keeps drinking.