6. The BigThree: Brainstorming
Discuss with a partner.What are the best examples you can
think of for:
1.) A wave being reflected
2.) A wave being absorbed
3.) A wave being transmitted through a medium
Discuss at your table.You have 5 MINUTES!Write your answers
(For you and your partner) on your post-it note
8. The BigThree: Brainstorming
Place your post-it notes under the appropriate categories on the
board!
Class discussion: What were some of your best ideas?
9. The BigThree: Reflection
Waves can be reflected
Reflection usually comes to mind when we think about light and
mirrors. However, all waves can be reflected.
11. The BigThree: Reflection
•Reflection is the change in direction of a wavefront at an
interface between two different media so that the
wavefront returns into the medium from which it
originated.
•The law of reflection says that for specular reflection the
angle at which the wave is incident on the surface equals
the angle at which it is reflected.
•In acoustics, reflection causes echoes and is used in sonar.
In geology, it is important in the study of seismic waves.
Reflection is observed with surface waves in bodies of
water.
14. The BigThree:Absorption
absorption of electromagnetic radiation is the way in which
the energy of a photon is taken up by matter, typically the
electrons of an atom.
The electromagnetic energy is transformed into internal
energy of the absorber.
Example: thermal energy
The reduction in intensity of a light wave propagating
through a medium by absorption of a part of its photons is
often called attenuation.
15. The BigThree:Transmission
Waves can be transmitted through different mediums
depending on the power of the wave, the wavelength and the
density of the object.
This ‘sand timer’ will start on a mouse click anywhere on the slide. The ‘sand’ will drain from the top section to the lower section and when completed will show the word ‘End’.To change the timings of this timer, you need to enter the animation settings, and change the timings for the Isosceles Triangles. There will be 2 that need changing (to the same amount) – one animates the top triangle emptying, whilst the other animates the bottom triangle filling.When you change the timings these have to entered as a number of seconds.
