What it shows
A covered jar in the sun warms faster than an open one. It is a simple model of how greenhouse gases keep heat near the Earth; the real atmosphere traps heat by absorbing infrared rather than by stopping air moving.
This idea has a short entry only. For the science behind it, read the sentence above with your textbook and ask your teacher to explain the law or idea it shows, so you can describe it in your own words.
Materials
- Two identical jars
- Two thermometers
- Cling film or a lid
- Sunlight or a lamp
- A notebook for readings
Safety
For this project: Use alcohol or digital thermometers, not mercury ones, and handle warm jars carefully. Never look at the lamp or the Sun.
Never use mains electricity: power models with cells, batteries or a low-voltage adapter. Sharp and hot tools, flames and lab chemicals need an adult or your teacher beside you. Keep magnets, button cells and small parts away from young children, and wash your hands after making.
How to go about it
Numbered steps have not been written for this idea yet. Plan it with your teacher: sketch the design with measurements, build one part at a time, test each part, and write every observation with the date. The free ebooks below have step-by-step projects of the same kind.
Free ebooks for this project
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