User:Steven J. Koch/Physics 102 Stuff/03 Jan 29

From WebCT

Hopefully by Thursday, you will have an increased understanding or intuition about matter and energy—both concepts which may seem easy at first, but then get a quite tricky when we really start trying to describe and define them. I think with this understanding growing (and it will keep growing throughout the semester), we are ready for the first big topic: Waves and Sound. Hopefully you can appreciate by Thursday that an understanding of sound requires some knowledge of both matter and energy.

Because sound travels in solids, liquids and gases, one may think we should become experts in chapters 12-14 (forms of matter) before trying to understand sound. But actually all we really need from these chapters as a prerequisite is some understanding of density and pressure. So for now we are skipping over these chapters for the most part, but we will come back to some concepts later in the semester.

Required reading:

Only three pages from chapters 12, 13, and 14 (Pressure and Density)

• Chapter 12, Page 232 (Density)
  • Newton (“N”) is a measure of weight, just like a pound, but in the metric system.
• Chapter 13, Page 248 (Pressure)
• Chapter 14, Page 274 (Pressure-density relationship and Boyle’s Law)
• A good check for understanding:
  • Review question 4 on page 244, Exercises 6 and 10 on page 245
  • Review question 2 on page 263
  • Review questions 13 & 14 on page 283

All of Chapter 19, Vibration and Waves, pages 362-376 (15 pages)

• There is a lot of material in this chapter, it will take you some time to read it all and think about new concepts.
• Make sure to spend enough time at the beginning of the chapter to achieve a solid notion of frequency and wavelength.
• You should pay more attention to being able to answer Review Questions 1-14 and less to Questions 15-28.