physical+properties+of+materials

=physical properties of materials=

Electrical conductivity/resistivity
media type="custom" key="10257727" Electrical conductivity (σ, in siemens per metre (S/m) ) is the ability of a material to conduct an electric current. Metals are generally good conductors while plastics and ceramics are not. Examples; Copper 5.96×10 7 S/m, Air 3 to 8 ×10 -15 S/m

Electrical resistivity ( ρ, in ohm metre (Ω·m)) is a measure of how strongly a material opposes the flow of electric current. Examples; Copper 1.68e−8 Ω·m, Glass 10e10 to 10e14 Ω·m

Specific gravity/density
Specific gravity (SG) is the ratio of the density of a material to the density of water Examples; Air 0.0012, Water 1, Iron 7.87, Gold 19.3

Density
Density (//ρ,// in kilograms per cubic metre (kg/m 3 )) or Mass Density of a material is defined as its mass per unit volume Examples; Water 1000 kg/m 3, Aluminium 2700 kg/m 3 , Titanium 4540kg/m 3 , Lead 11,340 kg/m 3

Thermal conductivity/expansion
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Thermal conductivity (//k// in watts per meters-Kelvin)//,// is the property of a material's ability to conduct heat Examples; Air 0.025 W/(m·K), Rubber 0.16 W/(m·K), Copper 401 W/(m·K),

Thermal expansion
Thermal expansion is a materials ability to change in volume with temperature. Examples of the coefficient of volumetric expansion //β// are; concrete 36 ×10-6/°C, Nickel 39 ×10-6/°C, Water 207 ×10-6/°C,

Specific Heat or Heat capacity
Heat Capacity is the amount of heat required to change a materials temperature by a given amount Examples; Air 1.0035 J/(g·K), Copper 0.385 J/(g·K), Water 4.1813 J/(g·K)

melting/boiling points
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Melting (or Fusion) is a change in a material from a solid to a liquid. An object that has melted completely is molten.

Examples of melting and boiling point temperatures: Note: The temperatures are in degrees Kelvin (K) K = °C + 273.15 (- 273.15 °C is absolute zero) To convert temperatures go to []
 * ====Material==== || ====Melting point==== || ====Boiling point==== ||
 * Iron (Fe) || 1808.15 K || 3134 K ||
 * Copper (Cu) || 1357.75 K || 2835 K ||
 * Tin (Sn) || 505.21 K || 2875 K ||
 * Gold (Au) || 1337.73 K || 3129 K ||

magnetic properties
The most important factor describing this property is ferromagnetism. This is whether the material will be attracted by a magnetic field. Four elements iron, nickel, cobalt and gadolinium and some alloys exhibit ferromagnetism.

optical properties
Colour and appearance can assist in identifying materials. Light striking the material can be reflected away, transmitted through or absorbed by it. Metal lustre is formed by only certain wavelengths of light being reflected. Some materials termed luminous, emit light.

How much do you remember? Complete the following quiz =quiz - physical properties= Make sure you have successfully completed the quiz

A valuable site for searching material online is http://www.matweb.com

We shall pause at this point to give you an opportunity to reflect on the course and your learning to this point Click on the following link =reflection 1=

=mechanical properties=