Chapter 1 Section 3

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Chapter 1 Section 3

Models definition of model Model is any representation of an object or an event used as a tool to understand the natural world.

Why are models necessary? • Hypothesis can be tested with models (instead of with an experiment) • Models are needed when what you are studying is too big or too small, or too dangerous, or expensive… • Models can help you visualize or understand how something works and therefore its function • Models can be used to show events that occur too slowly or too quickly to see – Ex: the Earth moving around the Sun

Types of Models • Most models fall into three basic types: • Physical • Computer model • Idea model

Physical Models *Models that you can see and touch are called physical models and they show how parts relate to one another. • Examples ????????

Computer Models • Computer models are built using computer software. • They can predict and calculate motions of hurricanes, positions of objects in the sky, and many other phenomenon that would take hours to calculate without a computer.

Idea Models *are ideas or concepts that describe how someone thinks about an ocurrence in the natural world. Some of these ideas can’t be turned into a physical model. Ex: mathematical formula

• Examples of models: Globes, maps, weather maps, recipes, math formulas that you are learning in school…. The Planets you did in 4th grade…

Models Save Time, Money, and Lives • Models can save lives: crash-test dummies are used in place of people when testing the effects of automobile crashes. • Models can save money and time: Models of new machines to see if they work before real production • Models can save time: idea models such as computer applications can save us a lot of time. Some calculations will take a long time to complete without a computer.

Limitations of Models *Models can change over time if more studies are done and more details are learned about the phenomenon or topic in question. EX?????? *The Solar system – our understanding of the Solar System changed over the years and also the models used to represent it