By definition, matter or material is anything that has mass and occupies space. Everything we see around us is matter.For example, a water bottle is made up of plastic or any metal, both of which are examples of matter. Lets discuss general and thermal properties of materials.
Matter has properties or characteristics, by which they can be identified. The major properties of materials can be categorized under:
- Mechanical properties of materials
- Chemical properties of materials
- Physical properties of materials
- Dimensional properties of materials
Thermal properties are those properties of a material which is related to its conductivity of heat. In other words, these are the properties which are exhibited by a material when heat is passed through it. Thermal properties come under the broader topic of physical properties of materials.
Thermal properties of a material decides how it reacts when it is subjected to heat fluctuation (excessive heat or very low heat, for example). The major components of thermal properties are:
- Heat capacity
- Thermal Expansion
- Thermal conductivity
- Thermal stress
Heat capacity of a material can be defined as the amount of heat required to change the temperature of the material by one degree. The amount of heat is generally expressed in joules or calories and the temperature in Celsius or Kelvin.
In order to calculate the heat capacity of materials with given dimension, Molar heat capacity or Specific heat capacity is used.
Heat capacity can be measured by the following formula:
is the amount of heat transferred,
is the change in temperature.
When heat is passed through a material, its shape changes. Generally, a material expands when heated. This property of a material is called Thermal Expansion. There can be change in area, volume and shape of the material.
For example, railway tracks often expand and as a result, get misshapen due to extreme heat.
It is the property of a material to conduct heat through itself. Materials with high thermal conductivity will conduct more heat than the ones with low conductivity.
For example, an iron rod will conduct more heat than normal window glass.
Some materials do not conduct heat at all because of the insulating properties of materials.
The stress experienced by a body due to either thermal expansion or contraction is called thermal stress. It can be potentially destructive in nature as it can make the material explode.
For example, cracks can be seen on roads where the heat is extreme. The crack is a result of thermal stress.
Refer to this link for NCERT Solutions of Thermal properties of Mass/Matter