Welcome to Physical Science!

What is Science? Science is a process Science is a process Science helps explain the natural world Science helps explain the natural world Science covers three main categories: Science covers three main categories: – Life Science – Earth Science – Physical Science

What is Science? Science uses observation and investigation Science uses observation and investigation Scientists use several methods Scientists use several methods – Observations are recorded – Experiments are conducted – Models are created and tested

What is Science? What do the methods have in common? What do the methods have in common? – They all involve collecting evidence – They all involve conclusions based on evidence A scientific question is one that can be answered by collecting and interpreting evidence A scientific question is one that can be answered by collecting and interpreting evidence

Is this a scientific question? Do all objects fall at the same rate? Do all objects fall at the same rate? – YES! What is the meaning of life? What is the meaning of life? – NO! Is our rain acidic or basic? Is our rain acidic or basic? – YES! In what color light do plants grow best? In what color light do plants grow best? – YES!

Is this a scientific question? Is the dress code at Athens Drive fair? Is the dress code at Athens Drive fair? – NO! Is it important to conserve energy? Is it important to conserve energy? – NO! What is the relationship between the frequency of a wave and its wavelength? What is the relationship between the frequency of a wave and its wavelength? – YES!

Observations You’re going to look at the next slide for 30 seconds You’re going to look at the next slide for 30 seconds After 30 seconds, we’ll list as many observations as you can remember After 30 seconds, we’ll list as many observations as you can remember You may write them down or not, but try to come up with as many as possible! You may write them down or not, but try to come up with as many as possible!

Galileo Galilei "All truths are easy to understand once they are discovered; the point is to discover them." "All truths are easy to understand once they are discovered; the point is to discover them." "You cannot teach a man anything; you can only help him discover it in himself." "You cannot teach a man anything; you can only help him discover it in himself."

We answer scientific questions and solve problems with 2 types of research. What are the two types? 1.Descriptive Research 2.Experimental Research

Based mainly on Observations Based mainly on Observations Used when experiments are impossible to perform Used when experiments are impossible to perform Involves the following: Involves the following: –Stating the research objective –Describing the research design –Eliminating bias DESCRIPTIVE RESEARCH

EXPERIMENTAL RESEARCH Experimental research includes investigations that: Have variables Have variables Test hypotheses Test hypotheses May have a control or control group May have a control or control group Is a set of planned steps Is a set of planned steps Tests one variable at a time Tests one variable at a time

Scientific Method The scientific method is an organized plan for gathering, organizing, and communicating information. The scientific method is an organized plan for gathering, organizing, and communicating information. The goal of any scientific method is to solve a problem or to better understand an observed event. The goal of any scientific method is to solve a problem or to better understand an observed event.

How do scientists OBSERVE? Using the 5 senses: Hearing Touch Smell Sight Taste

Observation 1. Observation – is information you obtain with your senses. 1. Observation – is information you obtain with your senses. What do you see? What do you see? What do you hear? What do you hear? What do you smell? What do you smell? What do you feel? What do you feel? What do you taste? What do you taste?

What you see The most direct way to gain knowledge about something in nature is to observe it. The most direct way to gain knowledge about something in nature is to observe it. Your ability to observe can be extended by using tools such as microscopes, telescopes, thermometers, and rulers. Your ability to observe can be extended by using tools such as microscopes, telescopes, thermometers, and rulers.

What you smell Many times scientists can identify the presence of a chemical, bacteria, or plant by its scent. Many times scientists can identify the presence of a chemical, bacteria, or plant by its scent.

Touch and Feel Texture –rough or smooth

Taste Determining concentration through taste Determining concentration through taste

What do you hear? Scientist record sounds of animals to determine how species communicate with each other. Scientist record sounds of animals to determine how species communicate with each other. Sounds Sounds

A common misperception of science is that science defines "truth". Science does not define truth, but rather it defines a way of thought. It is a process in which experiments are used to answer questions. This process is called the scientific method and involves several steps:

Scientific Method: A systematic approach to ____________ problems.

The Scientific Method involves a series of steps that are used to investigate a natural occurrence.

Step #1 What’s the problem anyway? Identify what Identify what you want to investigate

Making a Question After evaluating your observations, ask a question. What do you want to find out? State the problem as a question. Make the question as specific as possible. After evaluating your observations, ask a question. What do you want to find out? State the problem as a question. Make the question as specific as possible.

Step #2 Research the problem Learn more about your subject Learn more about your subject

Step #3 Form a Hypothesis What do you What do you think your experiment will show

Hypothesis A hypothesis is a proposed answer to the question you formulated. A hypothesis is a proposed answer to the question you formulated. A hypothesis is an educated guess at the possible answer to the question. A hypothesis is an educated guess at the possible answer to the question. What do you think is the cause of the problem you are studying? State a logical answer to your question. This answer, which is your hypothesis, should give one possible explanation for the cause. What do you think is the cause of the problem you are studying? State a logical answer to your question. This answer, which is your hypothesis, should give one possible explanation for the cause.

Step # 4 Design an experiment to test your hypothesis Find out if you are correct Find out if you are correct

Planned Experiment Scientist perform experiments to test their hypothesis. Scientist perform experiments to test their hypothesis. An experiment must be accurate and précised in order to be reproducible. An experiment must be accurate and précised in order to be reproducible. Accuracy – the closeness of a measurement to the true value of what is measured. Accuracy – the closeness of a measurement to the true value of what is measured. Precision – is a gauge of how exact a measurement is. In other words, to you get the same results each time or are the measurement values very close each time you measure. Precision – is a gauge of how exact a measurement is. In other words, to you get the same results each time or are the measurement values very close each time you measure.

Components of an Experiment Variable – in an experiment any factor that can change is called a variable. Variable – in an experiment any factor that can change is called a variable. Manipulated Variable – the variable that causes a change in another. Manipulated Variable – the variable that causes a change in another. Responding Variable – the variable that changes in response to the manipulated variable. Responding Variable – the variable that changes in response to the manipulated variable. Control Experiment – has two test groups- the control group and the experimental group. The control group is the standard by which any change can be measured. Control Experiment – has two test groups- the control group and the experimental group. The control group is the standard by which any change can be measured.

Vocabulary Constant – The factors that are kept the same. Constant – The factors that are kept the same. Variable – The factor that is changed by the person doing the experiment Variable – The factor that is changed by the person doing the experiment Investigative tools Investigative tools

Researching an Experiment List the materials necessary to conduct the experiment List the materials necessary to conduct the experiment Design the steps and procedures for the experiment. Design the steps and procedures for the experiment. Design how data will be collected. Design how data will be collected.

Why are REPEATED TRIALS necessary in an experiment? To make sure results are valid To make sure results are valid The more trials conducted, the more likely the results are reliable The more trials conducted, the more likely the results are reliable To make sure a “fluke” is not considered the true result To make sure a “fluke” is not considered the true result

Step # 5 Record and analyze your data

What is Data? Data is information we collect Data is information we collect

Data Tables A way to record results and observations accurately A way to record results and observations accurately Have a descriptive title Have a descriptive title Divided into columns & rows Divided into columns & rows Shows the independent variable Shows the independent variable Provides a place to record the dependent variable Provides a place to record the dependent variable How to RECORD DATA

Reduce the data with the best measure of central tendency Reduce the data with the best measure of central tendency Graph the data Graph the data Look for patterns and relations Look for patterns and relations Look at the shape of the graph Look at the shape of the graph Evaluate – Do you see any trends or patterns in the data? Do the data support your hypothesis or prediction? Do you need more information? Evaluate – Do you see any trends or patterns in the data? Do the data support your hypothesis or prediction? Do you need more information? How to ANALYZE DATA

Presentation of Data Information obtain from observation can be presented in a variety of forms to make it easier for the viewer to obtain facts quickly. Information obtain from observation can be presented in a variety of forms to make it easier for the viewer to obtain facts quickly. Graphs and charts present are some ways to organize and present data. Graphs and charts present are some ways to organize and present data.

Step # 6 State a conclusion Was your Was yourhypothesiscorrect?

What do scientists do when they DRAW CONCLUSIONS? Answer the original question Answer the original question State whether or not the hypothesis was supported (it is never “right” or “wrong”) State whether or not the hypothesis was supported (it is never “right” or “wrong”) Pose questions for further research Pose questions for further research

Drawing a Conclusion State your conclusion based on your data. Your data should either support your conclusion or lead you to another hypothesis. Have any new questions or problems come up? State your conclusion based on your data. Your data should either support your conclusion or lead you to another hypothesis. Have any new questions or problems come up?

Step # 7 Repeat your work to verify Prove you Prove you Were right

VARIABLE A part of an investigation that can be CHANGED

What is the VARIABLE? Control Experimental

3 TYPES OF VARIABLES 1.Independent Variable 2.Dependent Variable 3.Controlled Variable

INDEPENDENT VARIABLE The variable that can be changed during an experiment The variable that the scientists chooses to change The variable that may cause a change in the dependent variable

DEPENDENT VARIABLE The factor that is being measured in an experiment The variable that is measured by scientists The variable that may change because of the independent variable

CONTROLLED VARIABLE (CONSTANT) Variable that stays the same during an experiment Variable that is controlled by the scientist Variable that is not allowed to change

Identify the variables in this investigation.

1. Students of different ages were given the same jigsaw puzzle to put together. They were timed to see how long it took to finish the puzzle.

What was the independent variable? Ages of the students Ages of the students –Different ages were tested by the scientist

What was the dependent variable? The time it to put the puzzle together The time it to put the puzzle together –The time was observed and measured by the scientist

What was a controlled variable? Same puzzle Same puzzle –All of the participants were tested with the same puzzle. –It would not have been a fair test if some had an easy 30 piece puzzle and some had a harder 500 piece puzzle.

2. An investigation was done with an electromagnetic system made from a battery and wire wrapped around a nail. Different sizes of nails were used. The number of paper clips the electromagnet could pick up was measured.

What are the variables in this investigation?

Independent variable: Sizes of nails Sizes of nails –These were changed by the scientist

Dependent variable: Number of paper clips picked up Number of paper clips picked up –The number of paper clips observed and counted (measured)

Controlled variables: Battery, wire, type of nail Battery, wire, type of nail –None of these items were changed

The higher the temperature of water, the faster an egg will boil.

Independent variable – temperature of water Independent variable – temperature of water Dependent variable – time to cook an egg Dependent variable – time to cook an egg Controlled variable – type of egg Controlled variable – type of egg

3. The temperature of water was measured at different depths of a pond.

Independent variable – depth of the water Independent variable – depth of the water Dependent variable – temperature Dependent variable – temperature Controlled variable – thermometer Controlled variable – thermometer

Designing Investigations

The greater the amount of soap in a soap and water mixture, the bigger a soap bubble can be blown. Design an investigation to test this hypothesis. Design an investigation to test this hypothesis. –Identify the variables –What exactly will be changed? How will it be changed? –What exactly will be measured? How will it be measured?

The farther a ball drops, the higher it will bounce. Design an investigation to test this hypothesis. Design an investigation to test this hypothesis. –Identify the variables –What exactly will be changed? How will it be changed? –What exactly will be measured? How will it be measured?

Why do scientists use MODELS? To save time and money when testing ideas that are Very large Very large Very small Very small Dangerous Dangerous Time-consuming Time-consuming

Theory vs. Law A theory or law in the world of science is a hypothesis, or many hypotheses, which have undergone rigorous tests and have never been disproved. There is no set number of tests or a set length of time in which a hypothesis can become a theory or a law. A hypothesis becomes a theory or law when it is the general consensus of the scientific community that it should be so. Theories and laws are not as easily discarded as hypotheses.

What is the difference between Science and Technology? Technology is the application of science; Science  gaining knowledge Technology  using knowledge