What would happen to the water temperature after the

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What would happen to the water temperatureafter the next 10 min? Would it continue cooling down forever?4.Did the water appear to heat up or cool downquicker? Why do you think this is so? Hint:Examine the slopes you calculated. 5.HypothesizeWhere did the thermal energy inthe water go once the water began to cooldown? Support your hypothesis.1.Does placing your thermometer at the top ofthe water in your beaker result in differentreadings than if it is placed at the bottom of the beaker? Explain.2.Hypothesize what the temperature changesmight look like if you had the followingamounts of water in the beaker: 50 mL, 250 mL. 3.Suppose you insulated the beaker you wereusing. How would the beaker’s ability to heatup and cool down be affected? 1.Suppose you were to use vegetable oil in thebeaker instead of water. Hypothesize what thetemperature changes might look like if youwere to follow the same steps and perform the experiment.2.If you were to take soup at room temperatureand cook it in a microwave oven for 3 min,would the soup return to room temperature in 3 min? Explain your answer.Real-World PhysicsGoing FurtherConclude and ApplyAnalyzeTo find out more about thermal energy, visit theWeb site: physicspp.comphysicspp.comData TableMass of waterInitial air temperatureFinal air temperatureChange in air temperatureTime (min)Temperature (°C)Heating or Cooling
334How It WorksThe Heat PumpHeat pumps, also called reversible air conditioners,were invented in the 1940s. They are used to heat andcool homes and hotel rooms. Heat pumps change fromheaters to air conditioners by reversing the flow ofrefrigerant through the system.1.ObserveTrace the flow of refrigerantthrough the entire system for bothheating and cooling. Start at the compressor.2.AnalyzeWould a heat pump be ableto heat an entire house when the out-side temperature drops to extremelycold levels? ThinkingCriticallyAir gratingCompressor pumprefrigerant1432Receiver: tankstores refrigerantFanmotorUnitcabinetAirflowfromroomsAirflow toroomsInsideOutsideAirgratingFan motor1CoolingThe thin capillary tube sprays liquid refrigerant into a larger coil inside.2CoolingValves 1 and 2 are opened and valves 3 and 4 are closed for cooling. The refrigerant flows downward. The inside coil functions as an evaporator and the outside coil functions as a condenser.3HeatingThe thin capillary tube sprays liquid refrigerant into a larger diameter pipe in an outer coil for heating.HeatingValves 3 and 4 are opened and valves 1 and 2 are closed for heating. The refrigerant flows upward. The inside coil functions as a condenser and the outside coil functions as an evaporator.45The fan cools the coil during cooling and warms the coil during heating.
12.1 Temperature and Thermal EnergyVocabulary• conduction (p. 315)thermal equilibrium (p. 315)• heat (p. 317)• convection (p. 317)• radiation (p. 317)specific heat (p. 318)12.2 Changes of State and the Laws of ThermodynamicsVocabularyheat of fusion (p. 324)heat of vaporization (p. 324)first law of

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