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Temperature: For objects #1 and #2 which are brought in contact, heat will flow from object #2 into object #1 if T 2

The Fahrenheit and Celsius scales use different numerical values for the freezing and boiling points of water. The Celsius degree is larger than the Fahrenheit degree. Temperature: For objects #1 and #2 which are brought in contact, heat will flow from object #2 into object #1 if T 2 > T 1 .

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Temperature: For objects #1 and #2 which are brought in contact, heat will flow from object #2 into object #1 if T 2

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  1. The Fahrenheit and Celsius scales use different numerical values for the freezing and boiling points of water. The Celsius degree is larger than the Fahrenheit degree.

  2. Temperature: For objects #1 and #2 which are brought in contact, heat will flow from object #2 into object #1 if T2 > T1. Fahrenheit: TF = (9/5)TC + 32 Celsius: TC = (5/9)(TF - 32) Kelvin: TK = TC + 273.2 Zero K = “absolute zero”; No physical system can get colder than this.

  3. The pressure plotted as a function of temperature for different amounts of different gases. When extended backward, the lines all intersect the temperature axis at the same point.

  4. One-hundred grams of room-temperature water (20°C) is more effective than 100 grams of room-temperature steel shot in cooling a cup of hot water.

  5. Specific Heat Capacity: How much heat is needed to increase the temperature of one gram of water by one degree C? Exactly 1 Calorie. 1 cal = 4.186 J (energy) Hence, the specific heat capacity is: Water 1.0 cal/gm/C Ice 0.49 Steel 0.11 It takes much less heat to raise the temperature of 1 gram of steel than 1 gram of water. Steel will not remove as much heat from your hot coffee; water is a better cooling agent.

  6. What is heat? It is the energy that flows from a hot object to a cooler one.

  7. Heat flows from the hotter object to the colder one when two objects at different temperature are placed in contact. The changes in temperature that result depend on the quantities of material and the specific heat capacity of each object.

  8. Adding heat to a mixture of water and ice at 0°C melts the ice without changing the temperature of the mixture.

  9. Will adding heat to a body always raise its temperature? No, there can be a change of phase. It takes 0.49 cal to raise 1 gram of ice from -1 C to 0 C. But, it takes another 80 cal to go from ice at 0 C to water at 0 C. Similarly, it takes 540 cal to go from 1 gram of water at 100 C to one gram of steam at 100 C.

  10. A falling mass turns a paddle in an insulated beaker of water in this schematic representation of Joule’s apparatus for measuring the temperature increase produced by doing mechanical work on a system.

  11. An object can get hotter by • adding heat to it • doing work on it! • Total energy is conserved. Heat is another form of energy.

  12. Lecture Quiz 21 - Question1: A beaker contains liquid water plus ice. Some time later, the ice is melted. One can conclude that: Heat must have been added to the beaker. Cold must have flowed out of the beaker. Work had to be done on the beaker. The amount of energy in the beaker increased. More than one of the above.

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