An animation to create day and night!
This photomontage allows us to turn on or off various light sources. We distinguish primary sources (the sun, the stars, or a lamp) and the secondary sources (the Moon or any reflecting object).
We also illustrate that shadows only appear in contrast to the supplementary light created by a source.
Learning objectives
To illustrate different kinds of light sources and their corresponding effects on a scene.
To explain how light sources cast shadows. To study the three elements of a shadow: the light source, the object, and the projection surface. To show that shadows can only appear by contrast.
To predict which one of the light sources will create a specific shadow.
To analyze the rectilinear path of light in order to explain a shadow.
How to use the animation
Click on a street lamp to switch it on/off.
Click on the Moon the same way.