this is only a test...

Since I had no time to write a blog entry on the train cuz I was writing a final exam instead, I present for your reading pleasure... a final exam on heat and thermodynamics.

PART ONE: ENERGY
1) What is energy? Give a definition if you can, then list several examples of various kinds of energy.

2) Imagine a car driving down the road at 50 mph. The car has kinetic energy. Where did the car’s kinetic energy come from? Where did THAT energy come from...? Trace the energy of the car all the way back to its origin, through as many transformations as you can.

PART TWO: THEORIES OF HEAT
1) Imagine the following scenario: You make hot cup of tea to help you stay up late and study for your physics final;. The phone rings. You set your hot tea down to go answer the phone. You come back a half hour later to find your tea is now lukewarm. Explain what has just happened in terms of the caloric theory of heat.

2) Now take the same scenario above and explain what has just happened in terms of the kinetic theory of heat.

3) What observations and experiments by Count Rumford led him to reject the idea of ”caloric” ?

4) Describe the experiment conducted by James Joule. What did this experiment demonstrate?

PART THREE: HEAT AND TEMPERATURE
1) What is the difference between heat and temperature?

2) You can safely reach into a 400ºF oven and touch the top of a cake with your finger to test and see if it is “done”. But if your hand touches the rack, or the cake pan, you will be burned. Why is it safe to touch the 400º cake and the 400º air, but not the 400º metal?

3) Suppose you have 1 kilogram of lead and 1 kilogram of water. The lead is heated to a temperature of 180ºC, while the water is at a temperature of 20ºC. The hot lead and the warm water are placed into the same container and allowed to reach equilibrium. Would you expect the final temperature of the water and lead to be…

A) greater than 50º?
B) less than 50º?
C) 50º?

Explain your answer. What additional information would you need to know in order to answer this question exactly?

PART FOUR: The Laws of Thermodynamics
1) State the First Law of Thermodynamics below...

2) State the “Zeroth” Law of Thermodynamics below. Why is this law necessary, and why is it numbered “0” instead of “1”?

3) State the Second Law of Thermodynamics in as many ways as you can. (In terms of entropy, in terms of engines, in terms of heat flow, etc...)

4) State the Third Law of Thermodynamics below…

5) Explain as best you can what physicists mean by the term “entropy”.

PART FIVE: Thermodynamics and Statistical Mechanics
1) Briefly describe the “Maxwell’s Demon” thought-experiment?. What point was James Clerk Maxwell trying to make with his scenario?

2) What are some of the practical and theoretical obstacles to achieving a temperature of "absolute zero"?

Very straighforward... no tricky questions. Anything less than a passing grade on this exam should be cause for shame.