In deze les zitten 20 slides, met interactieve quizzen, tekstslides en 1 video.
Lesduur is: 50 min
Onderdelen in deze les
Shadow (p. 22)
Bluetooth
- On
Stationary
- Books
- Pen and pencil
- iPad
Report
- NO
Lessonup
- Yes
Bags in
the cuboard
Phones in the phone holder
Slide 1 - Tekstslide
Lesson goals:
Explain what light rays, partial shadow and full shadow is.
Name the types of light beams and explain their uses:
Divergent light beams
parallel light beams.
Explain what a point source is.
Slide 2 - Tekstslide
Light rays
Light rays move in straight
lines.
Light rays only become vissible when they reflect off other objects, e.g. During a lightshow, there needs to be smoke particles present in the air otherwise you dont see the laser beams.
A shadow forms when objects block light rays.
Slide 3 - Tekstslide
Why is the sky blue?
Light form the sun is scattered
when it enters our atmosphere.
This is called diffuse light.
Blue is scattered more than
the other colours, and therefore the more prominent colour.
Slide 4 - Tekstslide
Activity 8 (p. 30)
We do it differently
Use the fluorescent tube above you as lightsource, and your hand as an object
timer
2:00
Slide 5 - Tekstslide
Types of shadow
Partial shadow: A shadow that
receives light from more lightsources.
Full shadow: The light from all lightsources is stopped by the lit-up object.
For work spaces sharp shadows are unpleasant. That is why they are usually equipped with fluorescent tube lighting.
Slide 6 - Tekstslide
Slide 7 - Tekstslide
Types of light beams
o Point source: Light comes from one place. o Divergent light beam:
Light rays spread out.
(point source) o Parallel light beam:
Licht rays dont spread out.
(laser)
Slide 8 - Tekstslide
With a divergent light beam all light comes from one point.
A
True
B
False
Slide 9 - Quizvraag
With a parallel light beam the shadow is always the same size as the object.
A
True
B
False
Slide 10 - Quizvraag
With a divergent light beam the shadow is the same size as the object.
A
True
B
False
Slide 11 - Quizvraag
You can never see light rays.
A
True
B
False
Slide 12 - Quizvraag
Partial shadow is the area where no light reaches.
A
True
B
False
Slide 13 - Quizvraag
How can we see light?
A
Reflection
B
Diffusion
C
Parallel
D
Dispersion
Slide 14 - Quizvraag
Explain why the sky is blue.
Slide 15 - Open vraag
Which part of the drawing is partial shade?
A
B
C
A
A
B
B
C
C
Slide 16 - Quizvraag
Slide 17 - Video
What kind of light beam was used to make this presentation?
A
divergent
light beam
B
parallel
light beam
C
convergent
light beam
Slide 18 - Quizvraag
Do the following questions:
20 t/m 23 (blz. 24)
In your writingbook
Rules:
- 10 minutes
- No talking
Finished early: search more shadow theatre on youtube, and see what you can say about the kind of light beam they use.
timer
10:00
Slide 19 - Tekstslide
In a nutshell:
You can only see light when it is reflected.
Shadows apear when light is blocked by objects. Partial shade forms when some light is blocked, but still other light raches the area where the shadow forms.