Ch. 12

Ch. 12

1. 3-4 students per table

2. Workbook & Textbook

3. Pencil / Pen

4. Start when quiet

Term # 1

Term # 1• Health and Safety Test• Woodshop Mapping• Technical Drawing• Homework

Bonus• Noise Maker

Sec. 4 Recupe

Thursday@ 3-4:30

Day 4@ Lunch

Ch. 12: Materials

1. Constraints & Deformations

2. Properties

3. Degradation and Protection

Text / Work Books

Text Book - p. 386

Work Book - p. 197

• Copy the following definitions

A CONSTRAINT

• Describes the effect of external forces on a material (p. 387)

Compression

• A material subjected to forces that tend to crush it is undergoing compression (p. 387)

Example of Compression

Tension

• A material subjected to forces that tend to stretch it is undergoing tension.

Example of Tension

•

Torsion

• A material subjected to forces that tend to twist it in undergoing torsion.

Deflection (bending)

• A material subjected to forces that tend to bend it is undergoing deflection.

Examples of Bending

Shearing

• A material subjected to forces that tend to cut it is undergoing shearing.

Multiple Constraints

Deformations

3 Types of Deformation

Elastic - p. 387

• The constraint leads to temporary change in the shape or dimensions of the material.

• When the constraint is removed, the material returns to its original form.

Plastic

• The constraint leads to a permanent change in the shape or dimensions of the material. Even when the constraint is removed, the material remains deformed.

Fracture

• The constraint is so intense that the material breaks.

Homework

• Work Book - p.197-198

Earphone: Part 1

• Earphone Deconstruction

• Links I.D

Earphone Deconstruction

• Find Partner

• Get Earphone, Screw Driver & Ruler

• Deconstruct & Measure ALL parts

• Document dimensions on hand-out

Links I.D.

• Read instructions

• Turn to pg. in Text book

• Complete hand-out • Hand-in once complete

Noise Maker

Bonus Term 2