Understanding Models and Sign Conventions in Physics, Exercises of Signals and Systems Theory

Download Understanding Models and Sign Conventions in Physics and more Exercises Signals and Systems Theory in PDF only on Docsity! What is a Model? Concept Test In this exercise, you are to: • Draft a definition (in writing) of a “model.” (one minute) • Discuss your definition with your partner. (one minute) • Draft a new definition (in writing), acceptable to both you and your partner. (one minute) Be certain that your definition includes both what a model is, as well as what it is used for. The final definition should be a single, well­written sentence. docsity.com What is a Model? Solution A model is a description of a physical system that may be used to predict or explain the behavior of the system. Fundamental principle: Use the simplest model that captures the important behavior of the system, under the conditions in which the model will be used. Note that a good model need not be simple — only as simple as possible while still capturing the important behavior of the system. For example, the models that are used to predict global warming are very complicated, as they must be to describe the very complicated Earth climate system. A model need not be mathematical. While most of the models you will see in this class are mathematical, many models are not. A wind tunnel model is a physical model of a larger object. Animal models (e.g., lab rats) are often used to model human physiology. docsity.com Sign Conventions Comfort Level Concept Test My comfort level with sign conventions is: 1. Very low — I really don’t understand how the conventions work 2. Low — I understand the rules to apply, but it doesn’t make sense to me 3. Moderate — I understand the rules, but need some practice to be comfortable 4. High — I understand the rules, and they make good sense 5. Very high — I understand completely, and could explain the convention to another student docsity.com Sign Conventions Comfort Level Solution 0 5 10 15 20 25 1 2 3 4 5 Number of Students A n sw er Lecture S2: Sign Convention Comfort Level The average response is better than 3 (moderate comfort level), but not much more. Still need to work on sign conventions. docsity.com