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Flashcards in Chapter 4 Deck (19):
1

Define: Density

Weight per unit Volume

2

Define: Specific Gravity

Density of a material relative to the density of water and is therefore a ratio with no units

3

Define: Thermal Expansion

Measures the change in length per degree of temperature. Length ratio.

4

Define: Melting Point

Temperature at which the material transforms from a solid to liquid state

5

Define: Freezing Point

Temperature at which the material transforms from a liquid to solid state

6

Define: Heat of Fusion

Amount of heat energy need to accomplish phase changes from solid to liquid and vice versa.

7

Define: Supercooled Liquid

When an element remains a liquid even at temperatures below its freezing point; due to nucleation of crystals not initiating immediately

8

Define: Solidus

In metal alloys, melting begins at a certain temperature (solidus), which continues to rise as full transition from solid to liquid occurs

9

Define: Liquidus

In metal alloys, when all material is in the liquid state, the temperature is referred to as (liquidus)

10

Define: Specific Heat

Quantity of heat energy required to increase the temperature of a unit mass of the material by one degree. (C: J/kg-K)

11

Define: Thermal Conductivity

"k": J/s-mm-K ; the capacity of a substance to transfer heat through itself by physicial mechanism

12

Define: Resistivity

Basic electrical property that defines a material's capability to resist current flow; "r".

13

Define: Conductivity

Basic electrical property that defines a material's capability to conduct current flow; "c".

c = 1/r

14

Define: Conductors

Metals with low resistivity.

15

Define: Insulators

Materials with high resistivities

16

Define: Dielectric

Term given to insulators to mean a "nonconductor of direct current". However, if the voltage is high enough, current will form an arc and pass.

17

Define: Superconductor

Exhibits zero resistivity and observed in certain materials at low temperatures approaching absolute "0".

18

Define: Semiconductor

Material whose resistivity lies between insulators and conductors; commonly used element: silicon. Useful in fabricating integrated circuits.

19

Define: Electrolyte

An ionized solution in which electrolytic conduction requires that current enter and leave the solution at electrodes (anode and cathode)