# Heat energy how much heat is dissipated out of the

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heat energy, how much heat is dissipated out of the system, and how much energy isneeded to increase the internal energy of the system we use the equation:Internalenergyequalsheatminuswork(∆U = Q –1.First law of thermodynamicsstated that energy is not created nor destroyedinto something else. This is based on the process that the change or to increasethe internal energy is equal to the amount of heat flowing the system minus thenet work done by the system.2.Internal energyis the sum of the mechanical potential and kinetic energies ofthe particles in the system.3.Adiabatic process- when the heat transfer of the system is equal to zero or noheat transfer at all since energy is used exclusively for work.What’s MoreNormally, heat transfer takes place from high temperature to low temperature orfrom hot to cold, which does not require mechanical energy to occur. How about thetransfer of heat from low to high temperature? Would this be possible? Yes, it is throughthe use of aheat pump,an instrument used to reverse the natural flow of heat orspontaneous process of heat transfer into a non-spontaneous processbyabsorbingheatfrom a cold space and releasing it to a warmer one.This process requiresmechanical energy input to take place. This supports the Second Law ofThermodynamics which states that heat will never flow from a cold temperature to a hottemperature object.W).Given:Q = unknown; ∆U = 80J; W = -120JSolution:Q = ∆U + WQ = 80 J + (-120 J)Q = - 40 J
Objective:
5Explain how heat pumps work as exemplified by an air-condition unit and arefrigerator.Materials:Diagrams of refrigerator and air condition cycleA.Refrigeration cooling cycle processFigure 3. Refrigeration cooling cycle processProcedure:Study the diagram above and its part. Answer the following questions (you mayuse any search engine).Guide Questions:Q 5. Explain how a refrigerator work.Q 6. How does an evaporator work?Q 7. What happen to the vapor in the compressor?Q 8. What is the function of the condenser?Q 9. What happens to the pressure and heat in the evaporator?Guide questions:Q 10.How does an air conditioning unit function?Q 11. Why does an air conditioning unit need mechanical input of energy to function?Q 12.How will you increase the efficiency rate of an air conditioning unit?Q 13.Why is it necessary for a heat pump like refrigerator and air condition unit tohave an inverter?Heat transfer in a refrigerator and air condition unit shows a spontaneousprocess that required a mechanical external energy. Since heat flows from lowertemperature to higher temperature. This conforms to the second law of thermodynamicswhich states that heat will never flow from cold temperature to a hot temperature object.That is why a heat pump is needed. A heat pump is an instrument that reverse thedirection of the heat flow. Just like a refrigerator and air condition unit.

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