Curved Mirrors - Concave and Convex

Concave or Convex

In an earlier post (Reflected Light) the kids learned that flat mirrors reverse images.

But not all mirrors are flat. Some mirrors are curved inward (concave). Some mirrors are curved outward (convex). This activity investigates curved mirrors.

Materials

shiny spoon(s)

Directions

• Have children PREDICT what they will see when they look into both sides of a spoon.
• Have children OBSERVE their own facial images using both sides of a spoon.
• Have them DESCRIBE their images. (Were they the same?)
• Have the children SKETCH what they saw on both sides of the spoon.

Concave

Convex

Explanation:

• On the hollow side of the spoon (which is like a concave mirror), your reflection will look bigger and be upside down.
• On the other side of the spoon that bulges out (which is like a convex mirror) your reflection will look smaller.

Follow-up
Have the children start to make a list of concave and convex mirrors that they observe in the home and neighborhood.


Examples:
Concave: most make-up mirrors, cosmetic mirrors, dentists' mirrors, telescopes
Convex: thumb tacks, passenger side mirrors in cars, security mirrors hanging from ceilings of stores, some sunglasses