Observe - Adventures in Reflection

In the previous section, you saw that opaque objects both absorb and reflect light.  The amount of light that is absorbed or reflected depends on the material.

A rough, dark surface (such as a black pile of dirt) absorbs more light than a smooth, shiny surface does.


A smooth, shiny surface (such as freshly fallen snow) will reflect more light than a rough, dark surface does.

Try this!

Take a piece of tinfoil and look at your reflection in it. Now, crumple up the tinfoil, and spread it out again. Can you still see your reflection in it? Does your reflection look the same?

Smooth, shiny surfaces reflect the light uniformly so that all the light rays move in the same direction. This is why we can see our reflections in smooth, shiny surfaces. Because rough and dull surfaces scatter the light that is reflected, our eyes do not see that as a clear reflection.


As you use reflection to help you in this adventure game, you will notice that light always reflects from a surface at the same angle it hit the surface. This predictable light behaviour is used in many applications such as in DVD players and fibre optics.

Question: How does light reflect from various surfaces?

Resources

Science Connection

Diamonds are cut carefully to maximize the amount of light reflecting from their cut surfaces. Diamond cutting is a skill that requires knowledge of angles and how light reflects from the surfaces to produce the most sparkle.