temperature

Temperature can be referred as a physical quantity representing the hotness and coldness of an object. A thermometer is an instrument used for measuring temperatures. The thermometer may be calibrated in many temperature scales or only one temperature scale. Celsius scale also called centigrade is the most applied scale. Kelvin and Fahrenheit's scales are also other commonly used temperature scales. Temperature is among the seven base quantities and its SI unit is kelvin. The widely used scale in technology and science is the Kelvin scale.

The coldest a body can get is at absolute zero temperatures where thermal motion would be zero. This is according to theories. However, a physical system that is actual or an object is incapable of attaining an absolute zero temperature. 0 kelvins is used to denote absolute zero on the Kelvin scale and -273.15 degrees Celsius on a Celsius scale and on a Fahrenheit scale, it is denoted by -459.67.

Temperature should be proportional to kinetic energy average of microscopic motions for an ideal gas. Temperature is relevant in many fields including;

• Biology
• Chemistry
• Physics
• Natural sciences
• Medicine and many other daily life aspects.

TEMPERATURE EFFECTS.

Most physical processes are influenced by temperatures including:

1. Sound speed. This is a product of absolute temperature’s square root.
2. Chemical reactions. Temperature influences both the extent and the rate of chemical reactions.
3. Thermal radiation. Temperature influences thermal radiation’s both properties and amount released from an object’s surface.
4. Physical properties. Temperatures affect the material’s physical properties, for instance, changing the phase.

TEMPERATURE SCALES.

Scales of temperature differ in the following ways:

1. The zero degrees point chosen and
2. Incremental units’ magnitude or scale degrees.

Common measurements of temperatures are done using the Celsius scale. In this scale, a reading of zero degrees Celsius is explained by the point of freezing of water. 100 degrees, on the other hand, represents the boiling point.

The international system accepted kelvin as the unit for measuring temperatures. The relationship between the Celsius scale and the Kelvin scale is that for every increase of 1 degree Celsius in the Celsius scale a corresponding increase of 273.15 kelvins follows in the Kelvin scale.

The Fahrenheit scale is commonly used in the United States. According to this scale, 32 Fahrenheit is the freezing point of water and at 212 Fahrenheit is the boiling point.

TEMPERATURE SCALE TYPES.

The different temperature scales can be classified as theoretical or empirical. Empirical scales are older, unlike the theoretically based scales which arose in the mid-nineteenth century.

1. Empirically based. These temperature scales depend on simple physical properties measurements of materials directly. Example: in a mercury thermometer it is restricted to measuring temperatures not below the freezing point of mercury and not above its boiling point. Despite these hindrances, the most widely used thermometers are empirical.
2. Theoretically based. These are based on theoretical arguments particularly those of quantum mechanics, kinetic theory and thermodynamics. They are used as standards for calibration for thermometers of empirical base.

HEAT CAPACITY.

When the transfer of energy to and from a body is heat only, the body state changes. These changes may include:

• Pressure increase
• Phase change
• Temperature increase and many others.

The heat capacity of a body is gotten by dividing the quantity of transferred heat with the change in temperature observed.