AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |
Back to Blog
Or the fact that when we mention speed we should technically speak of the average of all the speeds of all the particles. Image of a thermometer.Īs always, there's much more to these concepts than what we've mentioned here, like for example the fact that speed is related to the kinetic energy by means of a square root. Jump to our particles velocity calculator and thermal energy calculator to learn more. This is very closely related to the concept of thermal energy and means that heat is just another expression of kinetic energy. What this means is that the higher the temperature of something, the higher the particles velocity a.k.a.the molecules that make up that something vibrate faster. There is no need to worry, however, because when we dig deeper into what is temperature, the answer is fairly simple: temperature is speed, or rather the momentum of the atoms and molecules that make up a material. To do this we have to turn to physics, in particular to thermodynamics and statistical physics, which is like thermodynamics meets quantum physics. We all know what is hot or cold, but temperature? Temperature is much harder to define without getting technical, which is precisely why we will get technical. Separate calculations are thus required using Equation 1 for the material below and above the phase change temperature.It is always hard to come up with a good definition for everyday terms, but with temperature, it is notoriously difficult. The Cp value (from Equation 1) of a material also changes with a change in state. How much energy is required to melt 50 lbs of lead?Ĭhanging state (melting and vaporizing) is a constant temperature process. Hv = Latent Heat of Vaporization (Btu/ lb ) Q D = Heat Required to Melt/Vaporize Materials Processed in Working Cycle ( Wh ) Q C = Heat Required to Melt/Vaporize Materials During Heat-Up ( Wh ) This same amount of energy is released as the vapor condenses back to a liquid. The latent heat of vaporization Hv of the substance is the energy required to change a substance from a liquid to a vapor. Another state change is involved in vaporization and condensation. The heat needed to melt a material is known as the latent heat of fusion and represented by Hf. Heat Required to Melt or Vaporize a Material In considering adding heat to a substance, it is also necessary to anticipate changes in state that might occur during this heating such as melting and vaporizing. How much heat energy is needed to change the temperature of 50 lbs of copper from 10☏ to 70☏? Heated media, work being processed, vessels, racks, belts, and ventilation air should be included. This equation should be applied to all materials absorbing heat in the application. ∆T = Temperature Rise of Material ( T Final – T Initial )(☏) Q B = Heat Required to Raise Temperature of Materials Processed in Working Cycle ( Wh ) Q A = Heat Required to Raise Temperature of Materials During Heat-Up ( Wh ) Since all calculations are in watts, an additional conversion of 3.412 Btu = 1 Wh is introduced yielding: Calling the amount of heat added Q, which will cause a change in temperature ∆T to a weight of substance W, at a specific heat of material Cp, then Q =w The specific heat capacity of a substance is the quantity of heat needed to raise the temperature of a unit quantity of the substance by one degree. Absorbed Energy, Heat Required to Raise the Temperature of a Material Because substances all heat differently, different amounts of heat are required in making a temperature change.
0 Comments
Read More
Leave a Reply. |