Chapter 1 Introduction to Science

DQ#1 - What is the job of all scientists? To improve our lives and the environment.

Science is the information from experimenting, researching and exploring all around us facts that can be tested and proven does not deal with a persons opinions or feelings

Results of Science provides explanations example: space, earthquakes new discoveries example: artificial limbs, new forms of energy new technology example: communication, better cars

Three Branches of Science Earth Science studies non-living parts of Earth ex. rocks, soil, oceans, atmosphere. geologist – rocks and minerals meteorologist – weather oceanographer - ocean

Physical Science studies chemicals, force, motion, energy ex. physicist – force and motion chemist – combines different chemicals to make new substances engineer - builds new structures and machines

Life Science studies living things ex. biologist – humans and animals botanist – plants

The Scientific Method 1.Make an observation using your five senses to gather information about what occurs. 2.Ask a question about what you observe and make an inference. An inference is a logical explanation based on prior knowledge.

3. Form a hypothesis A hypothesis is a possible explanation or prediction that can be tested. Example: If I put out 3 different brands of dog food, then Rocky will eat brand A, because it is made with better ingredients. A

4. Test your hypothesis (several ways) design a model (large items, too far away) gather evidence and record data making observations conducting an experiment

If you test your hypothesis using an experiment, you have to establish a variables. A variable is any factor that can have more than one value. An Independent Variable is the factor that you want to test. It is changed by the scientist to see how it affects the dependent variable

Controlled variables are all the other variables at the start of the experiment that remain the same. observe or measure The Dependent Variable is the factor you observe or measure after the experiment. When the independent variable is changed it causes the dependent variable to change.

5. Record and organize the data or results from the experiment Data is organized into tables or charts so that it is visually easy to read and understand.

6. Analyze the data To analyze means to by examine the graphs and look for any trends or relationships in the data. It will help explain the results of the experiment. Example: Analyzing the data shows that cats are owned by more students than any other pet.

7. Make a Conclusion A conclusion is a summary of the experiment to determine if the original hypothesis was correct. If the hypothesis is supported repeat the experiment several times to confirm results. If the hypothesis is not supported, revise (change) the original hypothesis and retest.

8.Communicate and share the results with others. This can be done by writing a scientific journal, speaking at conferences, the internet

Sample Experiment 1. Observe The flowers in my garden are growing at a different rate. 2. Ask a question What is causing some plants to grow quicker than others? 3. Form a Hypothesis If I put different amounts of water in two identical plants, then the plant with more water will grow quicker, because plants require water to grow.

4. Test your hypothesis (Experiment) Possible variables are the amount of sunlight, size and type of pot, type of soil, type of plant, and amount of water The independent variable - Water All others are controlled variables-same for both plants The dependent variable - height of the plant Week 1 Week 2 Week 3 A B A B A B

5. Record and Organize the Data Plant Growth (original height = 1 inch) Week 1Amount of water (cups) Height of Plants (inches) A12 B01 Week 2Amount of water (cups) Height if Plants (inches) A13 B01 Week 3Amount of Water (cups) Height of Plants (inches) A15 B01.5

6. Analyze the Data According to my data, I see a relationship between the amount of water given the plant and the amount of growth in the plant. 7. Make a Conclusion In conclusion, my hypothesis was supported by the experiment. Plant A grew higher than plant B because it received more water. 8. Communicate Results Write and turn in a lab report.

Clean up that Mess! Observation: The dirty table needs to be cleaned. Question: Which paper towel is the strongest?

Research Least expensive strong and absorbent Medium priced Thirst pockets Highest priced 2x stronger

Form a Hypothesis If I stack _______batteries on brand ______, then it will prove to be the strongest, because ___________________.

Test your Hypothesis Independent variable is _________ Controlled variables are ___________________ Dependent variable is __________ 1. Cover the container with a wet paper towel 2. Stack batteries one at a time on the paper towel 3. Record the number of batteries the paper towel can hold

4. Change the independent variable 5.Repeat steps 2-4 Design a graph showing your Data (bar graph would show the data the best) Analyze the Data According to my data, Brand ___ held the most batteries.

Conclusion My hypothesis was (supported or not supported). Brand ____ was the strongest paper towel because_____________. Communicate Results Turn in you Lab Report

Measurement and the Metric System

International System of Units (Metric System) scientists in different parts of the world used different units of measurement Made things confusing

In 1960, scientists adopted a new system of measurement The International System of Units (SI) is the universally accepted system of measurement except for the US, Liberia, and Burma

Volume the capacity or amount of space something takes up. base unit is the liter measured with a graduated cylinder

A liter (l)is approximately ½ a big bottle of soda A milliliter (ml)is approximately 20 drops of a liquid

Mass the amount of matter in an object base unit is the gram measured using a triple-beam balance

A gram (g) is approximately the weight of a paper clip. A kilogram (kg) is approximately the weight of a large book.

Length the distance between two places base unit is the meter (m) measured using a meter stick

1 kilometer (km) = a little more than ½ mile 1 meter (m) = a little more than 3 feet

1 centimeter (cm) = about the width of your pinky finger 1 millimeter (mm) = about the thickness of you ID tag

A ruler has inches on one side and centimeters (cm)and millimeters (mm)on the opposite side.