LESSON 3


ROTATION

(FIXED DEGREES)

OBJECTIVES: The students will know the difference between a "fixed" rotation and a "dynamic" rotation. The students will be able to execute a "fixed" rotation of a sketched object around one center point, then around two unique center points.

PROCEDURE:

(1) Lecture

(2) Discussion/answer questions

(3) Individual Work on computer

LESSON/CLASSWORK:

I. REVIEW OF YESTERDAY'S WORK

A. Translation by vectors

B. Translation by angles

II. ROTATION

A. What is rotation?

(1) Movement around a central point

(2) Movement by units of degrees

B. Two methods

(1) Fixed (today's study)

(2) Dynamic (movable)

C. Fixed Rotation

(1) You supply the degrees (set unit)

(2) The degree-unit remains constant until you change the setting

(3) Rotation may occur clock-wise or counterclock-wise

(4) Use Transform Menu

D. Steps around one fixed center point

(1) Construct a center point and an object to be transformed by rotation

(2) Highlight the center point

(3) Click "Transform" on the menu bar

(4) Click "Mark Center" from the drop-down box

(5) Highlight object to be rotated

(6) Click Transform on menu bar, then Rotation from the drop-down box

(7) Enter unit of desired degrees in provided box; click OK

(8) The object has (hopefully) rotated!

E. Steps around two fixed center points

(1) Rotation around two center points begins where the rotation around one center point ends

(2) Do the above steps (1) through (8)

(3) Construct another center point that the already-rotated object will rotate around

(4) Repeat steps (2) through (7), entering a new measurement of degrees, if desired

(5) Hopefully, step (8) has been repeated

F. Results

(1) Original object remains the same (initial step)

(2) Object's image is rotated around the center point (around one center point)

(3) Object's image has rotated around the second center point

III. WRAP-UP

A. Regroup

B. Review today's work

IV. DISMISS

 

 

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