P1- Topic 1: Key Words

6. This is when waves bounce off of a surface.
9. Complete this equation: Wave Speed = __________/ Times.
10. When a wave crosses the interface (boundary) between two different materials its speed changes. This is called _________.
11. Planets in our Solar System actually orbit the Sun. This is known as a _____________ model.
15. This is the type of lens that is wider in the middle than at the edges.
16. In a reflecting telescope there is one lens and two _________.
17. Waves transfer information and _________ without transferring matter.

1. Most of our information about our Solar System, the Milky Way and the Universe comes in the form of _______.
2. Astronomers can use this to compare and monitor how planets and stars move over long periods of time.
3. These waves move at right angles to the direction of the wave. An example is light waves.
4. Complete this equation: Wave Speed = __________ x wavelength.
5. Galileo observed the moons of this planet and it supported the new model of the solar system.
7. These waves move parallel with the direction of the wave. An example of these is sound waves.
8. The early astronomers thought that the Sun, Moon and planets moved in orbits around the Earth.__________ Model.
12. This lens in a telescope magnifies the image.
13. This lens in a refractive telescope, converges the waves to form an image.
14. The _________ length of a lens is the distance between the lens and where the image is focused.