# Rotational Symmetry

## Rotational Symmetry

A shape has Rotational Symmetry when it still looks the same after some rotation (of less than one full turn).

Rotational Symmetry

Order 2

Rotational Symmetry

Order 3

How **many times it matches** as we go once around is called the **Order**.

Think of propeller blades (like below), it makes it easier.

## Examples of Different Rotational Symmetry Order

Order | Example Shape | Artwork |
---|---|---|

(using Symmetry Artist) | ||

... and there is also Order 5, 6, 7, and ... | ||

... and then there is Order 9, 10, and so on ... |

Try rotational symmetry yourself with Symmetry Artist ... !

## Is there Rotational Symmetry of Order 1 ?

**Not really!** If a shape only matches itself **once** as we go around (ie it matches itself after one full rotation) there is really no symmetry at all ...

... because the word "Symmetry" comes from * syn- together* and

*metron*and there can't be "together" if there is just one thing.

**measure**,

## Real World Examples

A Dartboard has Rotational Symmetry of Order 10 | The US Bronze Star Medal has Order 5 | The London Eye has Order ... oops, I lost count! |