Topic 4 Properties of materials + smart materials

Question 1

Physical properties

Answer 1

these are characteristics of materials that can be identified through testing.

Question 2

Mass

Answer 2

relates to the amount of matter that is contained with a specific material. Mass is constant

Question 3

Weight

Answer 3

depends on mass and gravitational forces to provide value.

Question 4

Volume

Answer 4

quantity of three dimensional spaces enclosed by some boundary

Question 5

Density

Answer 5

mass per unit volume of a material.

Question 6

Electrical resistivity

Answer 6

measure of a materials ability to conduct electricity. something with a low resistivity will conduct electricity well.

Question 7

Thermal conductivity

Answer 7

how fast heat is conducted through a slab of material.

Question 8

Thermal expansion

Answer 8

measure of the degree of increase in dimensions when an object is heated.

Question 9

Hardness

Answer 9

defined as the resistance a material offers to penetration or scratching. Ceramic floor tiles are extremely hard.

Question 10

Tensile strength

Answer 10

ability to withstand pulling forces

Question 11

compressive strength

Answer 11

ability of a material to withstand being pushed or squashed

Question 12

Stiffness

Answer 12

resistance of an elastic body to deflection by an applied force

Question 13

toughness

Answer 13

ability of a material to absorb energy and plastically deform without fracturing

Question 14

ductility

Answer 14

ability of a material to be drawn or extruded into a wire or other extended shape

Question 15

elasticity

Answer 15

tendency of solid material to return to original shape after being deformed.

Question 16

Malleability

Answer 16

metal to be hammered into thin sheets. not seen in non-metals

Question 17

plasticity

Answer 17

ability of a material to be changed in shape permanently

Question 18

stress

Answer 18

force/cross sectional area

Question 19

strain

Answer 19

extension/stretched length

Question 20

Youngs modulus

Answer 20

measure of stiffness of an elastic material

Question 21

Smart materials

Answer 21

~~~~~~~~~~~~

Question 22

piezo electricity

Answer 22

pressure on piezoelectric material generates electricity

Question 23

Shape memory

Answer 23

allows severe deformation of a material which can then be retuned to its original shape by heating

Question 24

photo chromic

Answer 24

material which changes colour when exposed to light

Question 25

thermoelectricity

Answer 25

converts heat directly into electrical energy

Question 26

magneto/electro rheostatic

Answer 26

materials which are fluid can change their viscosity using magnetic or electric field.