Physics 2 c

Physics 2 c

1. Light has a shorter wavelength than infrared.

2. Hot objects emit infrared radiation.

3. Glass, and the greenhouse gases, let light through

4. Glass, and the greenhouse gases, don’t let infrared through.

5. As the number of greenhouse gases increases, less infrared can get out and so the Earth warms up.

6. The greenhouse gases are carbon dioxide, water vapour and methane.

7. Natural sources of carbon dioxide include: respiration, forest fires and volcanic eruptions.

8. Man-made sources of carbon dioxide include: burning of fossil fuels, deforestation; waste incineration and cement manufacture.

9. Natural sources of methane include: when organic material decays.

10. Man-made sources of methane include: the mining and burning of fossil fuels, farmed animals like cattle and rice paddies.

11. Water vapour mainly occurs naturally.