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The World of Physical Science

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Section 1 Exploring Physical Science

Section 2 Scientific Methods

Section 3 Scientific Models

Section 4 Tools, Measurement, and Safety

Chapter 1

Concept Mapping

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Section 1 Exploring Physical Science

Bellringer

One afternoon you decide to pop some popcorn. You put the bag in the microwave, but after a couple of minutes of cooking, it is clear the popcorn is not popping. Why did this happen? What steps could you take to help locate the problem?

Write your answers in your science journal.

Chapter 1

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Section 1 Exploring Physical Science

Objectives

• Explain that science involves asking questions.

• Describe the relationship of matter and energy to physical science.

• Describe the two branches of physical science.

• Identify three areas of science that use physical science.

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Section 1 Exploring Physical Science

That’s Science!

• Science is a process of gathering knowledge about the natural world.

• Everyday Science Learning to do everyday actions requires making observations and asking questions, which is what science is all about.

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Section 1 Exploring Physical Science

What is Physical Science?

• Physical science is the study of matter and energy

• Matter is the “stuff” everything is made of. Energy is the ability to do work.

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Section 1 Exploring Physical Science

What is Physical Science?

• A Study of Matter and Energy You will learn more about energy and matter as you explore physical science. Learning about matter and energy will help you answer questions such as:

• Why will paper burn and gold will not?• Why is throwing a bowling ball harder than throwing a baseball?• How can water turn into steam and back into water?

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Section 1 Exploring Physical Science

Branches of Physical Science

• Physical science is usually divided into chemistry and physics. Both of these can be further divided into specialized areas of study. • Chemistry––A Matter of Reactions! Chemistry is the study of al forms of matter, including how matter interacts with matter.

• Physics––A Matter of Energy! Physics looks mostly at energy and the way that energy affects matter

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Section 1 Exploring Physical Science

Physical Science: All Around You

• What you learn about matter and energy is important for other science classes, too.

• Meteorology The study of the Earth’s atmosphere, especially in relation to weather and climate, is called meteorology.

• Meteorologists must understand high and low pressure, motion, and force before the can predict the weather.

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Section 1 Exploring Physical Science

Physical Science: All Around You, continued

• Geology The study of the origin, history, and structure of Earth is called geology.

• Geochemist are geologists who apply their knowledge of heat, force, and chemistry to understand how rocks and soil change over time.

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Section 1 Exploring Physical Science

Physical Science: All Around You, continued

• Biology Biology is the study of life. Chemistry and physics explain many things that happen in biology.

• A chemical reaction explains how animals use sugar and oxygen to produce carbon dioxide and water and to release energy.

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Section 2 Scientific Methods

Bellringer

How can you prove that the world is not flat?

Write your answers in your science journal.

Chapter 1

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Section 2 Scientific Methods

Objectives

• Explain what scientific methods are.

• Explain how scientific methods are used to answer questions.

• Describe how a hypothesis is formed and tested.

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Section 2 Scientific Methods

Objectives, continued

• Identify methods that are used to analyze data.

• Explain how a conclusion can support or disprove a hypothesis.

• List methods of communicating data.

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Section 2 Scientific Methods

What Are Scientific Methods?

• The ways in which scientists answer questions and solve problems are called scientific methods.

• As scientists look for answers, they often use the same steps. But there is more than one way to use the steps. Scientists may repeat some steps or do them in a different order.

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Section 2 Scientific MethodsChapter 1

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Section 2 Scientific Methods

Ask a Question

• Asking a question helps focus the purpose of an investigation. Scientists often ask a question after making observations.

• An observation is any use of the senses to gather information.

• Observations should be accurately recorded so that scientists can use the information in future investigations.

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Section 2 Scientific Methods

Ask a Question, continued

• A Real-World Question Engineers are scientists who put scientific knowledge to practical human use.

• Engineers create technology. Technology is the application of science for practical purposes.

• For example, engineers Czarnowski and Triantafyllou studied the efficiency of boat propulsion systems.

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Section 2 Scientific Methods

Ask a Question, continued

• The Importance of Boat Efficiency Efficiency compares the energy used to move the boat forward with the energy supplied by the engine. Making boats more efficient would save fuel and money.

• Based on their observations, Czarnowski and Triantafyllou asked the question: How can boat propulsion systems be made more efficient?

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Section 2 Scientific MethodsChapter 1

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Section 2 Scientific Methods

Form a Hypothesis

• Once you have asked a question and made observations, you are ready to form a hypothesis.

• A hypothesis an explanation that is based on prior scientific research or observations that can be tested.

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Section 2 Scientific Methods

Form a Hypothesis, continued

• Nature Provides a Possible Answer Czarnowski studied penguins swimming and formed the hypothesis: A propulsion system that mimics the way a penguin swims will be more efficient than a propulsion system that uses propellers.

• Make Predictions Before scientists test a hypothesis, they often make predictions that state what they think will happen during the actual test of the hypothesis.

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Section 2 Scientific MethodsChapter 1

Hypothesis

Click below to watch the Visual Concept.

Visual Concept

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Section 2 Scientific Methods

Test the Hypothesis

• After you form a hypothesis, you must test it. Testing helps you find out if your hypothesis is correct or not.

• Keep It Under Control One way to test a hypothesis is to do a controlled experiment. A controlled experiment tests one variable at a time. By changing only the variable, scientists can see the results of just that one change.

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Section 2 Scientific Methods

Test the Hypothesis, continued

• Testing Proteus Czarnowski and Triantafyllou built a model penguin boat called Proteus to test their hypothesis.

• The engineers took Proteus into open water to collect data. Data are pieces of information acquired through observation or experimentation.

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Section 2 Scientific Methods

Analyze the Results

• Once you have your data, you must analyze them to find out whether the results support your hypothesis. The graphs below show the analysis of the tests done on Proteus.

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Section 2 Scientific Methods

Draw Conclusions

• At the end of an investigation, you must draw a conclusion. Your conclusion can help you decide what you do next.

• The Proteus Conclusion Czarnowski and Triantafyllou found that the penguin propulsion system was more efficient than a propeller system. So, they concluded that their hypothesis was supported.

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Section 2 Scientific Methods

Communicate Results

• One of the most important steps in an investigation is to communicate your results accurately and honestly.

• Communicating About Proteus Czarnowski and Triantafyllou published their results in academic papers. They also displayed their project and its results on the Internet.

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Section 3 Scientific Models

Bellringer

To teach cardiopulmonary resuscitation (CPR), instructors often use a mannequin to model a human upper torso and head. Why do you think CPR is taught with a model instead of a real human? Would the class be as effective if a model were not used? Explain your answer.

Chapter 1

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Section 3 Scientific Models

Objectives

• Explain how models are used to represent the natural world.

• Identify three types of scientific models.

• Describe theories and laws.

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Section 3 Scientific Models

Types of Scientific Models

• A representation of an object or a system is called a model.

Chapter 1

• Physical Models look like they thing they represent. For example, the model flower shown at right can be used to learn the parts of a real flower.

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Section 3 Scientific Models

Types of Scientific Models, continued

• Mathematical Models are made up of mathematical equations and data. The weather map shown below is a mathematical model.

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Section 3 Scientific Models

Types of Scientific Models, continued

• Conceptual Models are systems of ideas or are based on making comparisons with familiar things to explain an idea.

• The big bang theory explains the origin of the universe. This theory is an example of a conceptual model.

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Section 3 Scientific Models

Models Are Just the Right Size

• Models are often used to represent things that are very small or very large.

• Models are useful for studying cells and particles of matter that are too small to see with the unaided eye.

• Models are also useful for studying objects that are too large to see completely, such as the Earth or the solar system.

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Section 3 Scientific Models

Models Build Scientific Knowledge

• Models are often used to help illustrate and explain scientific theories.

• In science, a theory is a unifying explanation for a broad range of hypotheses and observations that have been supported by testing.

• Theories and models can change as new observations are made.

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Section 3 Scientific Models

Models Build Scientific Knowledge, continued

• Scientific Laws When a theory and its models correctly predict the results of many different experiments, a scientific law could be formed.

• In science, a law is a summary of many experimental results and observations.

• Laws are not the same as theories. Laws tell you only what happens, not why it happens.

Chapter 1

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Bellringer

How would a standard system of weights and measures, agreed to and used around the world, make life easier? Give examples.

Write your answers in your science journal.

Section 4 Tools, Measurement, and SafetyChapter 1

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Objectives

• Identify tools used to collect and analyze data.

• Explain the importance of the International System of Units.

• Identify the appropriate units to use for particular measurements.

• Identify safety symbols.

Section 4 Tools, Measurement, and SafetyChapter 1

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Tools in Science

• To get the best measurements, you need the proper tools. Stopwatches, metersticks, thermometers, and balances are examples of tools for measuring.

• Tools are also used to analyze data. Calculators, computers, and even pencils and paper, are tools you can use to analyze your data.

Section 4 Tools, Measurement, and SafetyChapter 1

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Making Measurements

• The International System of Units (SI) is the current name for the metric system. It is used by most scientists and almost all countries. All SI units are based on the number 10.

• Length The basic SI unit of length is the meter (m). Other SI units of length are larger or smaller than the meter by multiples of 10.

Section 4 Tools, Measurement, and SafetyChapter 1

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Measurement, continued

• Mass is the amount of matter that something is made of. The kilogram (kg) is basic SI unit for mass.

• Volume is the amount of space that something occupies. The volume of liquids are usually given in liters (L) or milliliters (mL). The volume of solids can be given in cubic meters (m3), cubic centimeters (cm3), or cubic millimeters (mm3).

Section 4 Tools, Measurement, and SafetyChapter 1

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Measurement, continued

• Density is the amount of matter in a given volume. Density can be expressed in grams per milliliter (g/mL) or grams per cubic centimeter (g/cm3).

• The equation for calculating density is:

density mass

volume

Section 4 Tools, Measurement, and SafetyChapter 1

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Measurement, continued

• Temperature is a measure of how hot (or cold) something is. Scientists often use degrees Celsius (°C) as the unit for temperature. Kelvins (K), the SI base unit for temperature, is also used.

• Common SI units and their conversions are shown on the next slide.

Section 4 Tools, Measurement, and SafetyChapter 1

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Section 4 Tools, Measurement, and SafetyChapter 1

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Safety Rules!

• Always follow your teacher’s instructions.

• Read lab procedures carefully and thoroughly.

• Pay special attention to safety information and know the safety symbols.

Section 4 Tools, Measurement, and SafetyChapter 1

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Use the terms below to complete the Concept Mapping on the next slide.

Concept Mapping

hypotheses

conclusions

observations

scientists

results

scientific methods

experiments

The World of Physical ScienceChapter 1

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The World of Physical ScienceChapter 1

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The World of Physical ScienceChapter 1