Temperature

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Temperature

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Heat (Heat) is one of the forms of energy, which is associated with the movement of atoms or molecules, or any particle enters in the composition of the article. Possible to obtain heat by chemical reactions Kalaanrac, or nuclear reactions nuclear Kanshar which occurs in the sun or the dissipation of electromagnetic, as in electric stoves or mechanical (motor), such as friction.

Heat that can move between objects by radiation or thermal conduction or convection. Temperature can not be transmitted between two objects or between two points in one object only if the temperature is different between them. Temperature is a measure of heat or coldness of an object.

Called the amount of heat needed to raise the temperature of an object one degree Celsius thermal capacitive. Heat capacity for each specific article and well known. Heat needed to raise the temperature of unit mass of a substance by one degree is called the heat quality is dependent on the situation of material and chemical structure. When fuel combustion issued a quantity of heat known as the calorific value of fuel and is usually estimated BTU. Through the process of turning pure substance from one state to another is lost heat or acquired without any change in temperature and know the amount of heat lost or gained during the transformation process on behalf of the latent heat and is directly dependent on the quality of material and condition of the primary and final.
Cover Click here to use the transformative agenda for the temperature

Unspeakable things, depending on the heated, as warm, and hot, and cold; be said on a sultry, or on a hot day, or very hot; also said the doctor, the patient's temperature rose. This category, relative; dealing with hot tea, while dealing with cold soft drinks; if tea was less colorful than usual, it was cool, and needs to heat up. And a sense of relatively warm air as well; temperature of 30 degrees Celsius, in the month of June, in the city of Riyadh, for example, make the day a moderate. But the degree itself, in the same place, in January, make a very hot day. And the human body temperature of a fixed standard, compared with high temperature or fall.

However, it is clear that there is considerable confusion between the concepts of temperature and degree; in spite of their importance and the widespread use them. Therefore, the first, at the beginning of research, to clarify the difference between them, and how to measure each; and identify a mechanism, which moves the heat from one object to another. Basically this is to consider the vertical distribution of temperature, in the atmosphere; and horizontal distribution, on the surface of the earth.

Temperature measurements
There are six standards for temperature, popularized the use of three of them, are:
Calvin, a measure Termdinameki; and scale percentile; and are used for scientific purposes. Fihrnhiti and scale, which is less common than its predecessors (for more detail on these standards, see Matin).
And three other measures, but commonly used, are:

Rankine scale Rankine Scale
Relies in the measurement of temperature, on the scale Fihrnhiti. And is expressed in degrees Rankine R. Is equal to degrees Fahrenheit; but zero degrees Rankine = absolute zero = -459.69 degrees Fahrenheit. This measure is attributed to the engineer in Scotland, William Franklin, John William John Frankline (1820 1872).

Measure Raimor Reaumur Scale

Expressing varying temperatures Raimor R. The points of the control, namely: the degree of melting ice, and equal to zero Raimor R; and the boiling point of water, equivalent to 80 Raimor. And is attributed to a French scientist, Rennes Anthony Raimor Rene Antoine Reaumur.

Practical measure of global temperatures International Practical Temperature Scale

The measurement on one of the ten control points. The points on which there are elements selected in ways the three (gaseous, liquid, solid), the so-called triple point Triple Pointe, at a certain pressure of these elements: hydrogen, oxygen, water, zinc, silver, and gold. Has identified three-point of water, at 273.16; and the degree of boiling, at 373.15.


The latent heat of fusion of solid body
Call the latent heat of fusion of pure body the amount of heat that must be provided for the unity of the mass of this body at the fusion temperature and under a certain pressure to convert it entirely to the liquid state at the same temperature and under the same pressure

Latent heat of vaporization of pure object
Call the latent heat of vaporization of pure liquid body at a fixed amount of warm temperature to be provided to unity the mass of this body in order to fully converted to steam and to keep the steam above the liquid is constant and equal to the saturated vapor pressure at the same temperature
Expansion of liquids with heat
Extend the types of rigid objects: extend longitudinally extended surface, volumetric expansion.
1) the linear extension of rigid objects: means the expansion in one dimension (length) only.
Definition of linear expansion: is the increase occurring in the length of the rigid body at high temperature.
Example of linear expansion: metal leg stretch, stretch the metal wire.
Coefficient of linear expansion (ml): * is the amount of the increase occurring on a length of the article, when a temperature of 1 ° C.
A unit of measurement is not: / m
Factors affecting the amount of linear expansion of metal leg:
1 - leg length: the greater the length of the leg increased the amount of stretching. (Positive relationship)
2 - The amount of rise in temperature: the higher the rise in temperature increased the amount of stretching. (Positive relationship)
3 - Type of material leg: the amount of expansion varies depending on the type material leg.
4) the laws of linear expansion:
1) L M = L 2 - L 1
For 1 (d 2 - d 1) is used to calculate the coefficient of linear expansion
Where:
For 1 cm by heating
Of 2 cm after the heating
D-1 temperature before heating
D 2 temperature after heating
2) for 2 - to 1 ml × l = 1 (d 2 - d 1) calculated the amount of linear expansion.
3) for 2 = l 1 (1 + ml (d 2 - d 1)) calculated length after heating.
4) d 2 - d 1 = L 2 - L 1
For a 1 × ml calculated as the rise in temperature.
** The device used to set the coefficient of linear expansion in practice: is a Alasveromitr
Fig (9 - 7), p. 14.
Expansion rigid surface of objects:
- Means the expansion in two dimensions (length and width) of any space.
Expanding the definition of surface:
Is the increase in the area of the rigid body at high temperature.
An example of the expansion surface:
Extend the metal plate.
Thermal expansion surface (cm):
Is the amount of the increase occurring on a unit area of the article, when a temperature of 1 ° C.
A unit of measurement MS: / M
The laws of surface expansion:
1) MS = x 2 - x 1
Q 1 (d 2 - d 1) factor is stretching surface.
Where: Q 1 space before the heating.
Q 2 space after heating.
D-1 temperature before heating
D 2 temperature after heating
2) x 2 - x 1 = x 1 cm × (d 2 - d 1) calculated the amount of surface expansion.
3) Q 2 = x 1 (1 + MS (d 2 - d 1)) is calculated after space heating.

4) MS = 2 ml factor is surface Bmallomip expansion coefficient of linear expansion.
- The expansion of gases by heat
Temperature change of the states of matter
For example, snow is in the solid state but what we are introducing the Movement melts and turns into a liquid (water )..... As well as water for introducing to the heat claimed the boil (evaporate) and Ithwol to a gaseous state (water vapor