Funny Reflections

What is symmetry and how do images reflect?

 

 

What is Needed

 

• Blank index cards with half words printed in upper case on each
• A flat mirror

 

 

What to Do

 

Choose one of the index cards that contains a word written so you see only half of it. Place the mirror vertically against the card and look at both the mirror and the index card. Do this for each of the words. What do you see? Will this work with any printed word? Which of the letters of the alphabet, when cut in half, will appear as the entire letter when the mirror is used?

 

 

What is Happening?

 

You are using a mirror to explore symmetry and to recognize symmetrical objects and printed letters. The image you see in the mirror shows you that all images are actually formed behind the mirror. These sorts of letters are called symmetrical and you are learning about a concept called symmetry. B, C, D, E, H, I, K O, and X are horizontally symmetrical.

 

 

 

 

 

Other Things to Try

 

You might explore the concept of longitudinal symmetry by using the letters A, H, I, M, O, T, U, V, W, X, and Y. How would you do this?

 

 

Purdue University Physics Department Physics on the Road Hands-on