1. Sect. 2, Ch. 1

2.  How long does it take for the energy from the sun to reach Earth?

3.  Roughly 8 minutes and 20 seconds.

4.  The Earth receives energy from the sun by radiation.  Radiation is the transfer of energy as electromagnetic waves.  Earth receives only about two-billionths of the energy radiated by the sun.  About 50 % of the sun’s energy actually reaches earth’s surface. https://www.youtube.com/watch?v=5GoZZKcNZiQ

6.  Thermal conduction is the transfer of energy through a material.  Example is touching a hot pan on a hot stove.  Thermal energy is always transferred from warm to cold areas.  https://www.youtube.com/watch?v=9joLYfayee8 https://www.youtube.com/watch?v=9joLYfayee8

7.  Convection is the transfer of thermal energy by the circulation or movement of a liquid or gas (fluids).  https://www.youtube.com/watch?v=VxGIiOTuAIs  https://www.youtube.com/watch?v=Gyj444FK0zs https://www.youtube.com/watch?v=Gyj444FK0zs

12.  The warming of the surface and lower atmosphere of Earth that occurs when water vapor, CO2, and other gases absorb and reradiate thermal energy.  Greenhouse gases function like the glass walls of a greenhouse which allow solar energy to enter but prevent thermal energy from escaping.

14.  A gradual increase in average global temperature.  Theory that increased greenhouse gases created by humans is increasing the greenhouse effect leading to warmer temperatures world wide.  Burning of fossil fuels and deforestation are the main contributors.  https://www.youtube.com/watch?v=ztWHqUFJRTs https://www.youtube.com/watch?v=ztWHqUFJRTs