Unit 8: Technology

Question 1

Deformation

Answer 1

Change shape

Question 2

Elastic deformation

Answer 2

Temporary change in the shape or size of the material; when constraint (force) is removed, the material returns back to its original shape

Question 3

Plastic deformation

Answer 3

Permanent change in the shape or size of the material; deforms and stays deformed

Question 4

Fracture

Answer 4

Material breaks

Question 5

Constraint

Answer 5

Effect of external forces on object

Question 6

Compression

Answer 6

Pushing together; crushing

Question 7

Tension

Answer 7

Stretching

Question 8

Torsion

Answer 8

Twisting

Question 9

Deflection

Answer 9

Bending

Question 10

Shearing

Answer 10

Cutting

Question 11

Mechanical property

Answer 11

How a material resists force; how a material reacts when subjected to constraint

Question 12

Compressive strength

Answer 12

Resists compression (pushing together)

Question 13

Tensile strength

Answer 13

Resists tension (Stretching)

Question 14

Shear strength

Answer 14

Resists shearing (cutting)

Question 15

Ductility

Answer 15

Metal stretching into wire without breaking during manufacturing process; deforms under tension (stretching)

Question 16

Malleability

Answer 16

Metal that flattens into sheet or bends without breaking during manufacturing process); deforms under compression; deforms under compression

Question 17

Hardness

Answer 17

Resists being scratched or deformed

Question 18

Plasticity

Answer 18

Does not return to its original shape after the stress (force)

Question 19

Stiffness

Answer 19

Retain its initial shape when subject to a force

Question 20

Toughness

Answer 20

Absorbs energy and plastically (permanently) deforms without fracturing

Question 21

Resilience

Answer 21

Resists shocks without breaking, often by deforming and returning to its original shape (elastically)

Question 22

Electrical conductivity

Answer 22

How well it conducts electricity; Ability to carry electric current

Question 23

Thermal conductivity

Answer 23

How well it conducts heat; ability to transmit heat; facilitates the transfer of thermal energy

Question 24

Heat resistance

Answer 24

How well it resists heat; ability to resist heat; inhibits the transfer of thermal energy

Question 25

Chemical neutrality

Answer 25

Ability to be chemically inactive; resist chemical reaction with substances

Question 26

Resistance to corrosion

Answer 26

Ability to resists the effects of corrosive substances; prevent formation of rust

Question 27

Lightness

Answer 27

Low-density materials

Question 28

Degradation

Answer 28

When material breaks down, due to effects of environment, causing them to lose their properties (e.g. compressive strength, ductility)

Question 29

Protection

Answer 29

Anything (typically protective coating) used to protect material to slow down or prevent degradation

Question 30

All woods are _ conductor of _ and _ (Except when they are _)

Answer 30

Poor, heat, electricity, wet

Question 31

Engineered wood (modified wood)

Answer 31

Made from sheets or pieces of wood stuck together with glue

Question 32

Wood can be destroyed by _,_, and _.

Answer 32

Fungus, insects,water

Question 33

Wood is protected using _ treatments and _ treatments.

Answer 33

Pesticide, heat

Question 34

Property of metals

Answer 34

- shiny - high heat and electrical conductivity

Question 35

Metals are extracted from _ by _.

Answer 35

Rock, mining

Question 36

Most metal objects are _, which contain a mixture of _.

Answer 36

Alloys, metal

Question 37

Metal _ when they react with oxygen and water.

Answer 37

Rust

Question 38

Protection of metal

Answer 38

- phosphates - painting - covering with grease

Question 39

Ceramics

Answer 39

- made of inorganic materials - produced by heating and cooling of the inorganic substances

Question 40

Properties of ceramic

Answer 40

- hard - brittle (can break) - low thermal conductivity - low electrical conductivity - waterproof (ceramic tiles) - good thermal insulator

Question 41

Degradation of ceramic

Answer 41

1. Acids and bases (may etch ceramics) 2. Physical and thermal shocks (may shatter ceramics)

Question 42

Protection of ceramics

Answer 42

- proper storage (low humidity) - chemicals (lie Pyrex) - cannot protect after objet is built

Question 43

Plastic is a material, often made from _ , that can be shaped and molded when _.

Answer 43

Petroleum, heated

Question 44

Two types of plastics are _ and _

Answer 44

Thermoplastics, thermosets

Question 45

Thermoplastic

Answer 45

Once they are formed, they can soften and melt if enough heat is applied

Question 46

thermosets

Answer 46

Once they are formed, they do not soften or melt no matter how much heat is applied

Question 47

Properties of plastic

Answer 47

- poor conductor of heat and elaecricity - thermosets are harder and more heat resistant than thermoplastics - thermosets are difficult or impossible to recycle

Question 48

Plastic can be degraded by _ , _, _.

Answer 48

Ultraviolet rays, oxidation, penetration by liquid

Question 49

Protection for plastic include _, _, _.

Answer 49

- waterproof coating, antioxidants, UV absorbing pigments

Question 50

Composite is a material made from _ materials.

Answer 50

Two or more

Question 51

Properties of composite are _ to properties of individual materials and can be _ to have desired properties

Answer 51

Superior, engineered

Question 52

_ material + _ material = composite

Answer 52

Matrix, reinforcement

Question 53

Composites degrade if component materials _ or if the _ between the components weakens.

Answer 53

Degrade, connection

Question 54

Properties of ceramics are (1) electrical conductivity, (2) thermal conductivity, (3) hardness, (4) elasticity, (5) chemical neutrality, (6) stiffness, (7) heat resistance, (8) corrosion resistance, and (9) resilience

Answer 54

1. Low or no 2. Variable 3. Very high 4. No 5. High 6. Very high 7. Very high 8. High 9. Low

Question 55

Properties of thermoplastics are (1) electrical conductivity, (2) thermal conductivity, (3) hardness, (4) elasticity, (5) chemical neutrality, (6) stiffness, (7) heat resistance, (8) corrosion resistance, and (9) resilience

Answer 55

1. No 2. Low 3. Variable 4. High 5. High 6. Variable 7. Variable 8. High 9. High

Question 56

Properties of thermosettingplastic are (1) electrical conductivity, (2) thermal conductivity, (3) hardness, (4) elasticity, (5) chemical neutrality, (6) stiffness, (7) heat resistance, (8) corrosion resistance, and (9) resilience

Answer 56

1. No 2. Variable 3. High 4. Variable 5. Variable 6. High 7. High 8. High 9. High