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Nature of Science – Unit 1Notes Packet

Vocab Introduction:Term or concept

Meaning Example

Science There are different kinds of sciences (biological, physical, earth and behavioral)

Technology application of science for practical uses

Model representation of an object or event that can be studied to understand the real object or event

Theory

Scientific Law

Truth valid everywhere in the universe; doesn’t provide explanations

Critical Thinking

Buy 2 small drinks, or 1 large?

Scientific MethodObservation Using the senses to study the

world.

Data Information gathered. Qualitative or quantitative

Hypothesis

Experiment Study factors / variables to find the cause / effect relationships

Variable Factor that can affect an experiment

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Independent Variable

Location of plants:window sillTablegreenhouse

Dependent Variable

Observed and measured during an experiment = the experimental data

Constant Each plant is given a 1/4 cup of water each day.

Control Plant given regular water instead of salt water

Metric System

Standard, worldwide system of measurement

Length Distance between 2 points

Mass a golf ball has more mass than a ping pong ball even though they are the same size

Volume A 2Liter soda

Density A lead ball the same size as a rubber ball, is more dense.

Weight measure of the force of gravity on an object.

Precision 4.11m is more precise than 4.1

Accuracy Description of how close a measurement is to the true value of the quantity measured

If a measuring tape has a broken tip, the measured value will not be accurate

Scientific Notation

We express very large or very small numbers as simple numbers, multiplied by a power

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of 10.Significant Figure

Helps determine the amount of rounding needed to show the precision of the measurement

You multiply 8.871 * 9.14 (dimensions of a room you are painting). The answer is 81.08094. Do you need all these numbers? No. Only as many as the least precise # you used, 9.14, so 3 digits. Round to 81.1

Key Ideas and Vocab Section 1Key Ideas:

1. How do scientists explore the world?2. How are the many types of science organized?3. What are scientific theories, and how are they different from scientific laws?4. What are scientific models and how are they used?

Vocabulary:Science LawTechnology TheoryModel

What is science? __________________________________________________________________________ Nature follows rules, and science is a method to understand those rules, and how and why they work. It is a process that uses observation (using your senses to gather information) and investigation to gain

knowledge about events in nature

Science is not…. ___________________________________________________________________________________ Pseudoscience is a claim, belief, or practice which is presented as scientific, but does not adhere to strict

standards of science (e.g. controlled variables, sample size, replicability, empirical and measurable evidence, and the concept of falsification). Example: __________________________________

Why do we do science? When you have a question about something, how something works…how do you find the answer? Research, Perform experiments using careful, methodical study, observe, confirm.

Scientists perform experiments to:1. ___________________________________________________________________________________2. ___________________________________________________________________________________3. ___________________________________________________________________________________4. ___________________________________________________________________________________

How science takes place…(draw the diagram)

Branches of Science Science: observing, studying and experimenting to find the nature of things. 2 main branches:

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Social science (individual and group behavior)o Examples: _____________________________________

Natural science (nature of the universe)Draw diagram:

Branches of science work together Today, the branches of science have become more mixed. What do you call someone who studies the chemistry of living things?

o ________________________________________ What do you call someone who studies the physics of the Earth?

o __________________________________________

What is the difference between science and technology? Pure science: ______________________________________________________________________ Technology: _______________________________________________________________________

o Ex: Revelations in science have allowed computers that used to fill entire rooms to become smaller, faster, and cheaper computers.

Laws and TheoriesLaw: describes a process in nature that can be tested by repeated experiments; allows predictions to be made about how a system will behave under a wide range of conditions; __________________________________ ________________________________________________________________________________________ ________________________________________________________________________________ Ex: if I place a hot cooking pot in a colder place, will the pot get hotter? No! It will always get cooler,

because there is a scientific LAW that says warm objects will always become cooler when placed in cooler surroundings.

_____________________________________________________________________________________ Area of a rectangle: A = l*w Universal Gravitation: F = G m1*m2 / r2

Theory: explanation of how a natural process works; explains many related observations and is ___________ ________________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ Can be added to or ____________________, if new evidence is validated and contradicts old theory

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Ex: In the cooking pot example, nothing explains WHY hot objects become cooler in cooler surroundings. This explanation must be provided by a scientific theory.

Always being questioned and examined –________________________________________________!!!! _____________________________________________________________________________________ To be valid, theories must continue to pass a series of tests.

o Must explain observations clearly and consistentlyo Experiments that illustrate the theory must be repeatable.o You must be able to predict results from the theory.

Models Model: ___________________________________________________________________________ Why? Sometimes models represent things that are too big, too small, or too complex to study easily. Outcome of models depend on the information put into them. Some examples of models:

o ______________________o ______________________o ______________________o ______________________

What is an example of a model that you can think of? _______________________________________

Section 1 Review1. Compare the two branches of physical science. __________________________________

__________________________________________________________________________________________________________________________________________________

2. Explain how science and technology depend on each other and how they differ from each other._______________________________________________________________________________________________________________________________________________________________________________________________________________________

3. Define scientific law and give an example. ________________________________________________________________________________________________________________________________________________________________________________________

4. Compare a scientific law and a scientific theory.____________________________________________________________________________________________________________________________________________________________________________________

5. Explain why a scientific theory might be changed. __________________________________________________________________________________________________________________________________________________________________________________

6. Describe how a scientific model is used and give an example of a scientific model. ________________________________________________________________________________________________________________________________________________________

Quiz next class!!

Key Ideas and Vocab - Section 2Key Ideas:

1. How can I think and act like a scientist?2. How can I design my own experiment?3. How do scientists measure things?

Vocabulary:

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Critical Thinking Scientific MethodsLength VariableMass VolumeDensity WeightMetric System

Science Skills- Identify problems- Plan experiments- Record observations- Report data- Critical thinking – ask questions, make observations, use logic – large or small popcorn- Creative thinking – to identify questions/problems, imagine and test solutions, be creative in the

approach to solving problems

Scientific Method A general way to organize your thinking about questions A series of steps followed to solve problems 7 Basic Steps of the Scientific Method

1. ___________________________________________________________________________2. ___________________________________________________________________________3. ___________________________________________________________________________4. ___________________________________________________________________________5. ___________________________________________________________________________6. ___________________________________________________________________________7. ___________________________________________________________________________

Scientific MethodStep 1: Observation _________________________________. Can also use tools such as previous research and computers.

Inference Inference: logical interpretation based on prior knowledge and past experiences. An explanation for an

observation you have made. _____________________________________________________________________________________ Usually has the word “______________________” in it.

Observation vs. Inference Observation: using the sense of sight and touch I observe that:

o The grass on the front lawn is wet. Why could it be wet? Possible Inferences

o _________________________________________________________________________________o __________________________________________________________________________________o __________________________________________________________________________________o __________________________________________________________________________________

All of these inferences could possibly explain why the grass is wet. They are all based on prior experiences. We have all seen rain, sprinklers, morning dew, and dogs going to the bathroom.

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Observationo The Fire Alarm is going off.

Why is this an observation? Make an inference: ____________________________________________________________

Step 2: Ask a question / conduct research Ask a question: Based on your observation, what do you want to know. Conduct research: figure out what is already known about your problem. Example:

o Observation: My dog is a picky eater.o Question: _____________________________________________________________________o Research: conduct research (computer based, interviews, journals) about what picky dogs like to

eat.

Step 3: Form a hypothesis A hypothesis is a prediction of what you think will happen, based on prior knowledge and the research

you have conducted (usually an if / then statement) _____________________________________________________________________ Example:

o Hypothesis: If I give my dog chicken flavored dog food, beef flavored dog food and duck flavored dog food, then she will eat the duck flavored dog food most of the time because research has shown that duck flavored dog food has a stronger smell.

In your hypothesis, you MUST state why you believe that is what will happen.

Step 4: Test your hypothesis by doing a controlled experiment Materials – What do you need to conduct your experiment? Procedure – sketch / step by step instructions of how you conduct your experiment so it can be repeated What would your materials and procedures be for the dog experiment?

_______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

In your experiment, you will have different variables. A variable is a factor that changes in an experiment in order to test a hypothesis

o Four different kinds of variables (factors) ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________

Variables that can affect the outcome of the experiment are kept constant, except the one(s) you want to measure. The more things you change at a time, the harder it is to make reliable conclusions.

Dog example: Dependent variable? ____________________ Constants?_____________________________Independent variable? ____________________ Control Group?_________________________

Another example- You might set up an experiment to determine which of three fertilizers helps plants to grow the biggest.

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- Possible factors include plant type, amount of sunlight, amount of water, room temperature, type of soil, and type of fertilizer.

Variables- In this experiment, the amount of growth is the dependent variable because its value changes

according to the changes in the other variables. (You use a tool to measure it)

- The variable you change to see how it will affect the dependent variable is called the independent variable. What is the independent variable?____________________________

Constants - A factor that does not change when other variables change is called a constant. - You might set up four trials, using the same soil and type of plant. - Each plant is given the same amount of sunlight and water and is kept at the same temperature.

These are constants.Control:

- The fourth plant is not fertilized- This plant is a control. A control is the standard by which the test results can be compared --

neutral point of reference for comparison

Constants and Controls - Suppose that after several days, the three fertilized plants grow between 2 and 3 cm.- If the unfertilized plant grows 1.5 cm, you might infer that the growth of the fertilized plants was

due to the fertilizers. The control is the plant that was unfertilized.

Step 5: Collect Data/Results- Need to organize data in a meaningful way.- A table, excel spreadsheet, graph or database are examples.- There are two different types of data, both of value

o Quant itative Data: _________________________________________________________________________________________________________________________________________________________________________________________________________________

The tree is 20 feet and 7 inches tall. The wind is blowing at 50 mph.

o Quali tative Data: ________________________________________________________________________________________________________________________________________

The tree is tall. The wind is blowing hard.

- Write three of your own examples for each. 1. ___________________________________________________________________2. ___________________________________________________________________3. ___________________________________________________________________

Quantitative or Qualitative??1. When the chemicals combined a gas formed. _____________ 6. I am 5’ 7” tall:____________2. The ph remained neutral at 7.____________ 7. It took 20 minutes to drive to school:_____________3. 95 degrees Farenheit= _______________________ 8. Prarie dogs are very social creatures:____________4. The waves were big= ________________________ 9. I slept for 7 hours:___________________5. The sky is blue = __________________________ 10. The blanket feels soft and fluffy:______________

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Step 6: Analyze and Draw Conclusions - Based on the analysis of your data, you decide whether or not your hypothesis is supported.- For the hypothesis to be considered valid and widely accepted, __________________________________

_____________________________________________________________________________________- What if your hypothesis is wrong?

o Try again, revamp your procedure / experiment.

Step 7: Repeat the experiment- To be valid, the results must be repeatable!

Being Objective- A bias occurs when what the scientist expects, changes how the results are viewed.- This expectation might cause a scientist to select a result from one trial over those from other trials. - Scientists can lessen bias by running as many trials as possible and by keeping accurate notes of each

observation made.- Valid experiments must have data that are _____________________________. - The experiment must be __________________________________.- Findings are supportable when other scientists perform the same experiment and get the same results.

Recap: Scientific Method – how it works 1. Scientists observe nature, then develop or revise hypotheses about how things work.2. The hypotheses are tested against evidence collected from observations and experiments.3. Any hypothesis that correctly accounts for all of the evidence from the observations and experiments

is a potentially correct theory.4. A theory is continually tested by collecting new and different evidence. Even one piece of evidence

that does not agree with a theory forces scientists to return to step one.

Scientists use special tools What would an astronomer use to study distant galaxies? _______________________________ Physicists use _________________________________ to make parts of atoms move very fast. Biologists use _________________________________ to study very small organisms and cells.

METRIC MANIA!!Length, Mass and Volume How do scientists measure things? Math is the language of science. So everyone is on the same page, scientists use standard units of measure We use the SI (International System of Units) to be consistent all over the world. Example: if you drink 3 gallons of water per week, and your friend drinks 350 ounces, who drinks more

water?

Some Base UnitsQuantity Unit Abbreviation

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SI Prefixes Look at a ruler. How would you express the length of a bird’s egg, or the distance you travelled on a

road trip in meters?o Bird’s egg may be 5/10ths of a meter or .05mo Road trip may be 800,000m

To avoid long numbers and lots of decimals we use prefixes for small and large numbers. All prefixes are in multiples of 10

Prefixes for LARGE measurements

Prefix Symbol Meaning Multiple of base unit

Prefixes for SMALL measurements

Prefix Symbol Meaning Multiple of base unit

Converting SI Unitso The width of a soccer goal is 7m. What is the width of the goal in centimeters?

Length ____________________________________________ The SI base unit for length is the ___________________ We use rulers or meter sticks to find the length of objects.

Work out Problem here….

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Use a ruler to draw and label 2 cm on your paper.

Mass _____________________________________________________________________________ A golf ball and a ping pong ball are the same size, but the golf ball has a lot more matter in it. So

the golf ball will have more mass. The SI unit for mass is the _______________________. A paper clip has a mass of about one gram. The mass of an object will not change unless we add or subtract matter from it.

Measuring Mass We will use a triple beam balance scale to measure mass. Gravity pulls equally on both sides of a balance scale, so you will get the same mass no matter

what planet you are on.

Weight _______________________________________________________________________________ Your weight can change depending on the force of gravity. The gravity will change depending on

the planet you are on. The SI unit for weight is the _______________________. The English unit for weight is the pound.

Volume _________________________________________________ We can find the volume of box shapes by the formula:

o Volume = length x width x height In this case the units would be cubic centimeters (cm3). So a box 2 cm x 3 cm x 5cm would have a volume of 30 cm3

Base Units The base unit for volume is the _________________ We measure volume with a graduated cylinder. Liquids form curved, upper surfaces when poured into graduated cylinders To correctly read the volume, read the bottom of the curve

called the meniscus

Water Displacement We can use water displacement to find the volume of

objects that are not boxed shaped. We can put water in a graduated cylinder. If a rock causes the level to rise from 7 to 9 ml, the the rock must have a volume of 2-mL.

Length: English vs. Metric UnitsWhich length is longer?

A. 1 mile or 1 kilometerB. 1 yard or 1 meterC. 1 inch or 1 centimeter

Draw and label box

Draw and label graduated cylinder

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The basic unit of length in the metric system in the meter and is represented by a lowercase m. Standard: The distance traveled by light in absolute vacuum in 1⁄299,792,458 of a second.

Metric Units 1 Kilometer (km) = 1000 meters 1 Meter = 100 Centimeters (cm) 1 Meter = 1000 Millimeters (mm

Which is larger?A. 1 meter or 105 centimeters C. 12 centimeters or 102 millimetersB. 4 kilometers or 4400 meters D. 1200 millimeters or 1 meter

Measuring Length: 1. How many millimeters (mm) are in 1 centimeter (cm)?______________________________

2. What is the length of the line in centimeters? _______cm3. What is the length of the line in millimeters? _______mm

4. In decimals, what is the actual length of the line? _______________cm5. What is the length of the line to the nearest centimeter? ________cm**HINT: Round to the nearest centimeter – no decimals.

Weight and MassJill Earth

1 gravityMoon1/6th gravity

Jupiter2.5 gravities

On orbit0 gravity

mass 30kg 30kg 30kg 30kg

weight

300N 50N 750N 0 Newtons

• Notice that Jill’s mass never changes. We cannot add to her or take away from her, so her mass stays the same. Jill is 30kg of little girl no matter where she goes!

• Her weight does change, because weight depends on gravity!!• Example: 10 N = 2.25 lbs.

Gravity• __________________________________________________________________________________• The force depends on two things: ______________________________________________________• more distance = less gravity = less weight

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• less distance = more gravity = more weight• more mass = more gravity = more weight• less mass = less gravity = less weight

Mass: English vs. Metric UnitsWhich is larger?

1. 1 Pound or 100 Grams2. 1 Kilogram or 1 Pound3. 1 Ounce or 1000 Milligrams

Mass refers to the amount of matter in an object. The base unit of mass in the metric system in the kilogram and is represented by kg.

Metric Units 1 Kilogram (kg) = 1000 Grams (g) 1 Gram (g) = 1000 Milligrams (mg)

Which is larger?A. 1 kilogram or 1500 grams C. 12 milligrams or 12 kilogramsB. 1200 milligrams or 1 gram D. 4 kilograms or 4500 grams

Volume: English vs. Metric Units

Which is larger? A. 1 liter or 1 gallonB. 1 liter or 1 quartC. 1 milliliter or 1 fluid ounce

Volume is the amount of space an object takes up. The base unit of volume in the metric system in the liter and is represented by L or l.

Metric Units 1 liter (L) = 1000 milliliters (mL) 1 milliliter (mL) = 1 cm3 (or cc) = 1 gram*

Which is larger?A. 1 liter or 1500 millilitersB. 200 milliliters or 1.2 litersC. 12 cm3 or 1.2 milliliters* (when referring to water)

We can measure the volume of regular object using the formula length x width x height.

_________*_________*_________=__________

We can measure the volume of irregular object using water displacement. Amount of H2O with object = ______ Difference = Volume = ______ About of H2O without object = ______

Draw the Box

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Density:

• Density is the mass per unit volume of a material or ________________________________________• Some things weigh more than others even though they take up the same space…so, lead is much more

dense than foam or wood.• Formula: _______________________________

Metric Conversion: The Ladder MethodHow do you use the “ladder” method? 1st – Determine your starting point.2nd – Count the “jumps” to your ending point.3rd – Move the decimal the same number of jumps in the same direction.

Draw and label the Ladder: (King Henry Died By Drinking Chocolate Milk)

Example: 4 km = _________ m Starting Point Ending PointHow many jumps does it take?4.___.____.___= 4,000m

Key Ideas and Vocab - Section 3Key Ideas:

1. Why is organizing data an important science skill?2. How do scientists handle very large and very small numbers?3. How can you tell the precision of a measurement?

Vocabulary:Precision Scientific NotationAccuracy Significant Figure

Draw a Table

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Organizing Data How would you organize data you are collecting? Example: You want to determine the average height

of people in your class. How do you collect& organize the data?

Why is it important? Keep track of data (what if you have thousands of people whose height you are tracking?) Be able to analyze the data and refer to it later. Share results with written reports and oral presentations.

Presenting Data Graphs are a great way to present data, but there are many kinds, each for a specific kind of data. ***Always, always title and label your graphs!!!

Line graphs1. Show continuous change2. Show something over time3. Dependent variable on y-axis4. Independent variable on x-axis

Bar Graphs Useful when you want to compare similar type data for several individual items or events. Used when you are comparing qualitative vs quantitative data

Pie Graphs Show the parts of a whole Shows percentages Percentages should = 100% (parts of a whole)

Histogram Show the frequency distribution of the data. The bars touch! Ex- using the numbers make a data table and histogram in your notes.

o 7, 12, 12, 18, 22, 24, 26, 27, 28, 29, 31, 36, 36, 39, 43, 47

Data Table Histogram

Draw a Line Graph

Draw a Bar Graph

Draw a Pie Graph

Draw a Table

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Scientific Notation Sometimes, numbers are too small or too large to write out. The speed of light is ~300,000,000 m/s How long does it take for light to get from Neptune to Earth (4,5000,000,000,000 m away)? Looking for time. t = d/s There are way too many zeros! We can express these as simple numbers, multiplied by a power of 10. Another way to write the speed of light is 3.0*108 m/s, and distance from Neptune, 4.5*1012 m. For small numbers, .001 would be written as 10-3

Precision and AccuracyPrecision: ______________________________________Example: If you are measuring the distance of two long jumps and are using a tape measure marked every .1m, you could report that both measurements were 4.1m. But if your tape measure marked every .01m, you could get more precise values. One jump was 4.11m and one was 4.14.

Accuracy: _________________________________________________________________________________________________________________________________________________________If, when measuring the long jump, you notice that the tip of the measuring tape is broken, you could still show 4.14m, but its not accurate. A measurement is only as accurate and precise as the tool used to make it.

Significant Figures: _____________________________________________________________________________________________________________________________________________The distance of 4.1m has two significant figures because the measured value has 2 digits. 4.14, 3 significant figures, because of 3 digits. Rule of thumb: when answering a problem, your answer should have as many significant figures as the number in your problem with the least amount of digits.

Practice – Section 3Round the following to two significant digits:1. 13,5892. 8893. .0002419494. .725

Answers:1.2.3.4.