Conceptual Physics Name: Jasmine BlairCh. 21 & 22 Date March 12, 2012Thermal Energy/Heat Day 1 - Information Gatheringhttp://www.sparknotes.com/testprep/books/sat2/physics/chapter12section1.rhtml

Directions:One worksheet per person.Go to the above website and find the answers to the following questions.Answer the questions using your OWN thoughts and words. You will lose points for just copying and pasting the answers from the website.If you need to find a photo/picture, copy/paste it by the question or attach it separately. Also, don’t forget to include the website where you found the photo.

Questions:1. Which 2 terms have a subtle difference when studying physics? Heat and Temperature

2. Heat is to temperature as money is to __________wealth___.

3. Temperature measures the amount of ________thermal energy ____ (heat) of an object.

4. Physicists use which temperature scale? Degrees Celsius a.k.a. Centigrade

5. Water freezes at _ exactly 0ºC___ Celsius and boils at ____100ºC____Celsius.

6. Another name for this scale is centigrade. Using what you know about metric prefixes,

Determine why this a good name for the scale.

7. The Kelvin scale (K) is a measure of __absolute temperature__.The Kelvin scale is always ___positive__.On the Kelvin scale the lowest theoretical temperature is called the

________absolute zero 0k________.

8. What is the definition of temperature? The measure of the average kinetic energy of the molecules that make up that material.

9. At what temperature do the molecules have zero kinetic energy? Absolute zero 0k

10. Do you remember what kinetic energy is? If not, look it up and write it down here.Kinetic energy is the energy of motion.11. Why is it impossible to get any colder than absolute zero? Because anything that has absolute zero temperature has zero kinetic energy, which is zero movement.

12. The kinetic energy of an object influences the state of matter of that object.In terms of kinetic energy, why are solids rigid? Because their molecules do not

have enough kinetic energy to go anywhere, they can only vibrate in place.

In terms of kinetic energy, why do fluids flow? Because the molecules have enough kinetic energy to move around one another but not enough to escape one another.

In a gas, the molecules have so much kinetic energy that they _disperse_______.13. Find (copy) a picture/photo that demonstrates the kinetic energy of the 3 states of matter.

14. What is the definition of heat? Is the measure of how much thermal energy is transmitted from one body to another.

15. Another name for heat is thermal energy. What is the unit of thermal energy? __joules__

16. What happens when you cuddle up with hot water bottle?

abyssinia.tradeindia.com it transmits a certain amount of heat to your body.

17. Heat is also frequently measured in ___________calories_.

18. Calories relate heat to ______________changes in temperature

19. How many Joules equals one calorie? _____4.19J__

How does this calorie DIFFER from a food Calorie? Calorie is the energy stored in the chemical bonds of food and calorie is the thermal heat energy.

20. Put a hot mug of cocoa in your hand, and your hand will get ___warmer while the mug gets ___cooler________. You may have noticed that the _______reverse_____ never

happens: you can’t make your hand colder and the mug hotter by putting your hand against the mug. What you have noticed is a general truth about the world: heat flows

spontaneously from a hotter object, but never from a colder object to a hotter object. This is one way of stating the Second Law of Thermodynamics__________________.

Whenever two objects of different temperatures are placed in contact, heat will flow from the hotter of the two objects to the colder until they both have the same temperature. When they reach this state, we say they are in Thermal equilibrium.

Because energy is conserved, the heat that flows out of the hotter object will be equal to the heat that flows into the colder object.

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21. On the above diagram indicate the direction of heat flow (label every vector).

22. You may have noticed in everyday life that substances can often expand or contract with a change in temperature even if they don’t change phase. How does this affect tuning a musical instrument? Because the length of the instrument and its pitch varies the room temperature.

23. Use the term thermal expansion to explain how a thermometer works.

Thermal Expansion is used in everyday life and its substance can often expand or contract and a thermometer work according to this principle

24. What are the 3 methods of heat transfer?

Conduction, Convention, and Radiation

25. How are the 3 methods similar?Because they all transfer heat between liquids and solids

26. How are the 3 methods different?Conduction has more to do with heat turning into gases, Convention has more to do with like a fan and its displacement with hot air and cold air, Radiation has more to do with microwaves (heating food)27. Find a picture/photo that indicates the similarities or differences between the 3 methods of heat transfer.