1. Yolanda López ESO 1 - TECHNOLOGIES

2. WHAT IS IT? A scale drawing represents something that is:  too large to be drawn to actual size OR  too small to be drawn to actual size

3. In other words, a scale drawing is eitherthe reduction or enlargement o f an object.

4.  Because we want the drawings to fit on a standard size piece of paper.

5.  Each scale drawing has a scale.  The scale is the ratio that compares the length of the drawing to the actual object.

6. 1:1 ONE TO ONE, FULL SIZE, OR LIFE- SIZED DRAWINGS  This means that 1cm on the paper is equal to an actual distance of 1cm.  You draw something in the same size it would be in real life. e.g. a CD case

7. 1:2  This means your drawing is half size of the original object.  1 cm on the drawing would be equal to 2 cm in real life. Which one is the original object? Why?

8. 2:1  2cm on the drawing equal 1 cm in real life.  This means the actual object is half size of the drawing.

9. Match 1:1DOUBLE SIZEThe drawing is the exact same size as the actual object 1:2HALF SIZEThe drawing is half the size of the artifact 2:1FULL SIZEThe drawing is twice as large as the artifact

10. Decide wether to enlarge or reduce these objects:  A cellphone  A marble  A lion  A salt crystal  A killer whale  An eraser  A glue stick  A knife  A sofa  A dragonfly  Eiffel tower  Rocket Full size Enlargement Reduction Enlargement Reduction Enlargement Full size Reduction Enlargement Reduction

11.  Let’s make a scale drawing: http://www.pcastela.es/recursos/oxford_dibujo/ _media/menuppal.html  HINT Multiply the length by the scale factor  1:2  scale factor = 0.5  2:1  scale factor = 2