Scenario – Harnessing the rotational symmetry dynamically in a design context
Evgenia Sendova Toni Chehlarova
What is the common feature of a woodcarved ceiling and a ceramics plate in the style of a Trojan drop? – A mathematical phenomenon known as a kfold rotational symmetry. To explore this concept you will use a Dynamic Software (GeoGebra in our case).
The Challenge: Create a virtual model of a woodcarved ceiling as the ones in Fig. 1
<Fig. 1>
Hint:
· Identify the smallest geometric element to undergo rotation so as to get a virtual model of original you have chosen to model.
· choose an angle of rotation and rotate the figure as many times as necessary to close the figure (rosette)
· Carry out an exploration for different angles of rotation and fill in the Table 1
· Write your conjecture and check it on p. XXX ()
Table 1
Angle 




Number of rotations 









Warming Up
Problem 2. What is the center and the angle of the rotation in Fig. 2.
Problem 3. Which ones of the figures have rotational symmetry?
1) 2) 3) 4) 5) 6) 7) 8) 9)
Verify your conjecture.
Problem 4. Which ones of the figures have rotational symmetry?
Problem 5. Generate a regular gon by means of a nfold rotational symmetry for:
а) ; б) ; в) ; г) ; д) ; е) ; ж).
Try to find different solutions.
· with a fixed angle of rotation
Visit our library of virtual models of ceilings:
<adres>