How do objects create shadows?


Targets
At the end of this unit, you should be able to answer the following questions:

1. Where is light found in our world? (sun, electric lights, objects that glow)

1.1 What objects emit their own light? What objects need a light source to be seen?

1.2 How is looking at the sun or bright light dangerous?
2. How does light interact with other materials?

2.1 How can we use light to classify objects as transparent, translucent, or opaque?

2.2 How do objects create shadow?
3. How does light travel?

3.1 What happens when light hits a surface? (absorbed, reflected, or refracted)

3.2 How can light be broken into colours or combined to make a new colour?

3.3 How do various optical devices work?
Targets
Looking at how various materials transmit light has shown you that light can do many things when it hits an object. Different materials may allow a different amounts of light to pass through.

REMEMBER: Transparent materials allow all light to pass through. Opaque materials do not allow any light to pass through. Translucent materials are somewhere between.

When light strikes an opaque object and cannot pass through, it makes a shadow. The shadow is a dark spot that indicates where the light is blocked. These pictures show some common examples of shadows.



Science Connection


Video

Click here to learn about: creating shadow puppets with your hands! By holding your hands in front of a light, you can make shapes that resemble the shadows of different animals.