WEEKLY READING ASSIGNMENTS:

Updated October 29: Here are the questions that you posed to me for this week. I'll discuss most of them in class this Thursday Oct. 31.

Reading for the week of Oct. 21-25: Please read chapter 3 (focusing on 3.61-3.70) and continue onto chapter 4 up to section 4.50. Please feel free to try the experiments related to section 4.6 (the liquid drop on a hot skillet, but don't stick your finger in molten lead) This winter, please try the experiments related to sections 4.33 and 4.34.

1. Please send me by email your weekly question by Sunday Oct. 20 at 6pm.
2. A question related to section 4.23: if the outside temperature is much below freezing, how quickly does an ice layer form on a still pond? Specifically: assume that the initial ice thickness is zero and the temperature is constant (and much below freezing). What is the dependence of the ice thickness on time?

Reading for the week of Oct. 7-11: Please finish reading chapter 2. There is a wealth of fascinating phenomena discussed that could occupy an entire course. Please focus on the following topics: 2.75 (splashing), 2.81 (pearling instability), 2.84 (drop spreading), 2.85 (cheerios attraction), 2.91 (coffee stains), 2.102 (sand cohesion), 2.107 (sand flow in an hourglass), 2.121 (dripping faucet), 2.137 & 138 (convection instabilities).

    Homework/discussion items for class on Oct. 10:

1. Please send me by email your weekly question by Monday Oct. 7 at 6pm. Updated October 7: for your reference, here are the questions that you posed to me for this week. I'll discuss most of them in class this Thursday Oct. 10.

2. If you eat cheerios, please perform the experiment of section 2.85.

For your viewing pleasure: this movie shows the splash of a liquid drop when it hits a flat solid surface with either 1 atm (left) or 0.2 atm (right) pressure. The movie was taken from the research page of Prof. Sid Nagel at the University of Chicago.

Reading for the week of Sept. 30 - Oct 4: Text, up to section 2.68. Please focus on 2.25, and 2.26: the concentration of tea leaves at the bottom of a cup of water that has been stirred and the meandering of rivers. Please be repared to discuss these topics in class.

For fun, here are a few photos from the book "An Album of Fluid Motion" by M. Van Dyke on fluid flow patterns around a cylinder/sphere for various Reynolds numbers.

For even more fun, here is a u-tube video that shows the collapse of the Tacoma Narrow bridge in 1940 (section 2.4 of the text).

   Homework/discussion items for class on Oct. 3:

1. Please send me by email your weekly question by Monday Sept. 30 by 6pm.
2. Using only a single sheet of 8.5x11 standard paper (and perhaps a small piece of scotch tape) construct a device that will sink as slowly as possible. You may cut your piece of paper to any shape as long as it is larger than 9 square inches. Brownie points will be awarded for the best airfoil.

Updated October 1: for your reference, here are the questions that you posed to me for this week. I'll discuss most of them in class this Thursday Oct. 3.

Reading for the week of Sept. 23-27: Finish chapter 1 of the text. Please focus on sections 1.24, 1.42, and 1.45, and be prepared to discuss these topics in class. Below is the homework for the week, as well as discussion items for class on Sept. 26.
   

1. Fill a glass to the brim with water and walk with it. Can you do so without spilling the water? What happens when you try the same thing using a shallow pan whose radius is a foot or more? (Perhaps you should try the second experiment outside.)
   
2. What is silly putty made from? If you have some, play with it and then answer the following question: Is silly putty a liquid or a solid?
   
3. Crumple some standard sheets of paper to as small a ball as you can. Uncrumple your samples and study the pattern of folds. What can you learn from this pattern?
   
4. Please ask one general question about physics that you personally would like to know the answer. Please provide this to me by Monday at 6pm, by a simple text email. I will answer as many as I can during the next class.

For your reference, here are the questions that you posed to me for this week.

Reading for the week of Sept. 16-20: Text, section 1.41-118. Focus on sections 1.49-53 and 1.73-77 and be prepared to discuss these two topics in class. Below are discussion items for class on Sept. 19:
   

1. Here is a movie of a masse shot. What is the cue ball trajectory mathematically?
   
2. An object falls in air due to gravity. How does the terminal speed depend on g, air density, and object shape?
   

   For your amusement and education: sketches of fluid flow past an obstacle for different flow speeds, and the drag force on a cylinder versus flow speed (from the Feynman Lectures on Physics vol. II).

3. (This problem is from an old Russian math olympiad). Consider two cannonballs of mass M that can move in one dimension and are approaching each other. There is a ping-pong of mass m«M in between (but not half way) the two cannonballs. Assume that all collisions are elastic and that all motion is in one dimension. The ping-pong ball is hit by one cannonball, then the other, etc., and gradually speeds up because of repeatedly rattling between the two cannonballs. Eventually the rapidly moving ping-pong ball causes the cannonballs recede from each other. How many collisions occur before the cannonballs recede?

Reading for the weeks of Sept. 2 & 9: Text up to section 1.40.
    Discussion item for class on Sept. 12: Here are time-lapse photos (1,2,3,4,5) of the blast wave from first atomic bomb test in July 1945.
    What was the energy released by this blast?