Question

The temperature $20{}^\circ C$ corresponds to ____________.

Answer 1

Temperature is a physical number that describes how hot or cold something is. When a body comes into contact with another that is colder or hotter, it is the manifestation of thermal energy, which is present in all matter and is the cause of the occurrence of heat, a flow of energy. A thermometer is used to determine the temperature. Thermometers are calibrated in a variety of temperature scales that have traditionally defined temperature using a variety of reference points and thermometric substances

Complete step by step solution:
The Kelvin and Celsius scales are the most frequently used temperature measuring scales in the thermometer business. One degree on the Kelvin scale has the same value as one degree on the Celsius scale, implying that the temperature difference or change is the same on both scales.
$Celsius\text{ }=\text{ }\left( Kelvin\text{ }\text{ }273.15 \right)$
or $Kelvin\text{ }=\text{ }\left( Celsius\text{ }+\text{ }273.15 \right)$may be used to convert Celsius to Kelvin.
To convert a temperature from Kelvin to Celsius, use the Kelvin to Celsius formula.
Given C = $20{}^\circ C$
$Kelvin\text{ }=\text{ }\left( Celsius\text{ }+\text{ }273.15 \right)$
$Kelvin\text{ }=\text{ }\left( 20\text{ }+\text{ }273.15 \right)$
$Kelvin\text{ }=\text{ }293.15\text{ }K$
The kelvin is the SI's (International System of Units) basic unit of temperature, denoted by the letter K. Thomson's conditions for an absolute thermodynamic temperature scale are met by the Kelvin scale. It has a null point of absolute zero (i.e. low entropy). Pure water freezes at 273.15 K and boils at 373.15 K on the Kelvin scale. The kelvin, unlike the degrees Fahrenheit and Celsius, is neither referred to or written as a degree. The kelvin is the fundamental unit of temperature measurement in the physical sciences, however it is frequently confused with the degree Celsius, which has a similar magnitude.

Note:
The kelvin is a unit of measurement for light sources' colour temperature. The idea behind colour temperature is that a black body radiator produces light with a frequency distribution that is proportional to its temperature. Black bodies look reddish at temperatures below approximately 4000 K, and bluish at temperatures beyond about 7500 K. In the disciplines of image projection and photography, where a colour temperature of roughly 5600 K is necessary to match "daylight" film emulsions, colour temperature is critical.