Temperature is a measure of the average kinetic energy of the particles in a substance. It is a physical quantity that determines the direction of heat flow and is typically measured in units of degrees Celsius (°C) or Kelvin (K).
While temperature and heat are often used interchangeably in everyday language, they are distinct concepts in science. Temperature is a measure of the average energy of particles, while heat is a measure of the total energy in a system. Temperature determines the direction of heat flow, with heat always flowing from a higher temperature to a lower temperature.
Absolute zero is the lowest possible temperature, at which the particles in a substance have no kinetic energy. It is equivalent to 0 Kelvin (K), or -273.15 degrees Celsius (°C). Absolute zero is significant because it is the basis for the Kelvin temperature scale, and it is the point at which all thermal motion stops.
The most commonly used units for temperature are degrees Celsius (°C) and Kelvin (K). However, in some contexts, temperature may also be measured in degrees Fahrenheit (°F) or Rankine (°R). These units are related by specific conversion formulas, with 0 °C equaling 32 °F and 0 K equaling -459.67 °F.
Temperature measurements can be affected by a variety of factors, including the type of thermometer used, the material and color of the object being measured, and the location and surrounding environment of the measurement. Additionally, temperature can also be influenced by factors such as pressure, altitude, and humidity, which can affect the thermal energy of a substance.