Bell work u Answer the following questions u

Bell work u Answer the following questions: u How is an airplane flight simulator a kind of model? u What are some advantages to training pilots in a flight simulator rather than in a real airplane? u Write your answers in your science journal-composition book.

Models

Objectives for Today! • Give examples of three types of models. • Identify the benefits and limitations of models. • Compare the ways that scientists use hypotheses, theories, and laws.

What is a Model u A model is a representation of an object or system. – Models often use familiar objects or ideas that stand for other things. Greeks were the first people known to make models of nature. u They used logic and geometry to explain patterns in nature without resorting to myth or the supernatural. u They sought to understand the architecture of the Universe by constructing models of nature. u

What is a Model u Keep in mind that models have limitations. – A limitation is how the model is not perfect. u Models are often used to represent things that are very small or very large. Particles of matter are too small to see. u Three major kinds of scientific models are physical, mathematical, and conceptual models.

Objectives for Today! • Give examples of three types of models. • Identify the benefits and limitations of models. • Compare the ways that scientists use hypotheses, theories, and laws.

Physical Models u Model airplanes, maps, and dolls are physical models. u Physical models of systems that can be easily observed and manipulated. u Have characteristics similar to key features of more complex systems in the real world. u A limitation of a doll as the model of a baby is that the doll doesn't act like a baby. Give an example of a physical model. u What are some limitations? u

Physical models

Mathematical Model u A mathematical model is made up of mathematical equations and data. – Simple mathematical models allow you to calculate things such as how far a car will go in an hour. – Other models are so complex that only computers can handle them. Involve solving relevant equation (s) of a system or characterizing a system based upon its statistical parameters such as mean, mode, variance or regression coefficients. u Using the most correct data does not make the prediction correct, this is a limitation. u A change in a variable that was not predicted could cause the model to fail. u Give an example of a mathematical model. u

Mathematical Model: A Punnett Square • The Punnett square helps scientists study the passing of traits from parents to offspring.

Projected Population Estimates 2005 5 year increments 2010 . Africa Asia Europe* N. A. 891 3, 913 729 512 S. A. O. +Aus. Total 371 32 6. 45 6. 8 2011 2012 2013 7. 00 7 B 7. 05 1 year increments 7. 10 2014 7. 15 2015 7. 2 2020 7. 6 2025 1, 327 4, 753 711 618 447 39 2030 2035 Nat. Geo. 7. 89 8. 2 5 year increments 8. 5 2040 8. 8 2045 9. 4 9 B 10. 5 B 2050. Estimated 2050 Pop. Distribution 2, 050 6, 109 458* 720 475 43 9. 85 20. 8% 62. 0% 4. 6% 7. 3% 4. 8% 0. 4% 99% * The data for Europe includes all of Russsia, except for 2050. -

Conceptual Model The third kind of model is a conceptual model. u Some conceptual models are systems of ideas. u Others are based on making comparisons with familiar things to help illustrate or explain an idea. u – One example of a conceptual model is the system that scientists use to classify living things. By using a system of ideas, scientists can group living things by what they have in common. This type of model allows scientists to better understand each group of living things.

Conceptual Model u People receive information, process this information, and respond accordingly many times each day. u This sort of processing of information is essentially a conceptual model (or mental model) of how things in our surrounding environment work. u Give an example of a Conceptual model.

Conceptual models u. Universe-everything –Galaxies- billions of stars grouped together u. Systems- 1 star and it’s orbiting bodies –Planet –Comets –Asteroids

Objectives for Today! • Give examples of three types of models. • Identify the benefits and limitations of models. • Compare the ways that scientists use hypotheses, theories, and laws.

What is a Theory? u u Models are often used to help illustrate and explain scientific theories. A theory is a unifying explanation for a range of hypotheses and observations that have been supported by testing. (Definition copy as is!) A theory not only can explain an observation you've made but also can predict what might happen in the future. Keep in mind that models can be changed or replaced. – These changes happen because new observations cause scientists to change their theories.

What is a Law? What happens when a theory and its models correctly predict the results of many different experiments? A scientific law could be formed. u A law is a summary of many experimental results and observations. u A law tells you how things work. u A law tells you to expect the same thing to happen every time. u

Objectives for Today! • Give examples of three types of models. • Identify the benefits and limitations of models. • Compare the ways that scientists use hypotheses, theories, and laws.