Introduction - Section 3

Targets

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

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?

Because you encounter light everyday, you already have a good idea of how light interacts with other materials.  You have seen how light can be blocked, or pass through various materials.  You have seen how light can bounce off of some materials.  When light behaves in these ways, we can see the effect of it (as in shadows or reflections).

Before we explore further how light travels, look again at what light actually is by clicking on the link below.

the video introducing the unit
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If you remember, light is a form of energy. Light radiates out in all directions from its sources and travels in a straight line until it hits an object.

What happens after that depends on whether the object is transparent, translucent, or opaque.

By learning about how light behaves, we can find out more about how we see colours, and we can apply this information in many ways. Devices such as cameras or microscopes are based on using our knowledge of how light travels.

You are about to find out more about what light can do. It's not just about shadows...