Temperature and heat

Temperature and heat

1. temperature

2. heat

3. temperature

   • temperature is an objective comparative measurement of hot or cold. It is measured by a thermometer. Several scales and units exist for measuring temperature
   • measurements
     • celisus
     • kelvin
     • farenheit
   • The Rankine Scale
     • For some engineering purposes, the Rankine scale is used. The degree size is the same as the Fahrenheit degree, and the zero of the scale is absolute zero. Often just R for "Rankines" is used rather than °R for expressing Rankine temperatures. The zero of the Rankine scale is -459.67°F (absolute zero) and the freezing point of water is 491.67R = 32°F.
   • Temperature Standard Points
     • While the typical treatment of temperature scales takes the freezing point of water to be 0C and the boiling point at standard pressure to be 100C, there are more precise treatments of standard points for defining temperatures. By international agreement, one standard point is the triple point of water which has been defined to be 273.16K. The freezing point of water at atmospheric pressure is .01K below this at 273.15K.

4. heat

   • heat is the amount of energy flowing from one body to another spontaneously due to their temperature difference, or by any means other than through work or the transfer of matter.
   • 1 calorie=4.1868 joules 1BTU= 1055.056 joules
   • internal energy
     • Internal energy is defined as the energy associated with the random, disordered motion of molecules. It is separated in scale from the macroscopic ordered energy associated with moving objects; it refers to the invisible microscopic energy on the atomic and molecular scale. For example, a room temperature glass of water sitting on a table has no apparent energy, either potential or kinetic . But on the microscopic scale it is a seething mass of high speed molecules traveling at hundreds of meters per second. If the water were tossed across the room, this microscopic energy would not necessarily be changed when we superimpose an ordered large scale motion on the water as a whole.
   • Thermal Equilibrium
     • Zeroth Law of Thermodynamics
       • The zeroth law of thermodynamics states that if two thermodynamic systems are each in thermal equilibrium with a third, then they are in thermal equilibrium with each other.
   • Amount of heat
     • he heat capacity of a defined system is the amount of heat (usually expressed in calories, kilocalories, or joules) needed to raise the system's temperature by one degree (usually expressed in Celsius or Kelvin). It is expressed in units of thermal energy per degree temperature.
       • Q = m•C•ΔT