Warm – Up Chapter 1 - 2 1. Describe the branches of Natural Science. 2. What is the goal of science? 3. What is the goal of technology? 4. What is the difference between a quantitative and a qualitative statement?

Scientific Investigation Video

Chapter 1 - 2 The Way Science Works

Critical Thinking Critical Thinking – The ability and willingness to asses claims critically and to make judgments on the basis of objective and supported reasons. Your lights go out. What do you do?

Scientific Method: 1.Observe your surroundings (5 senses) 2.Formulate a Question 3.Research – Collect as much information as possible 4.Form a Hypothesis – Educated Guess – Based on your research 5.Test your Hypothesis – Experiment 6.Observe and Collect Data 7.Draw Conclusions – Was your hypothesis correct?

Scientific Method You use the Scientific Method! You wake up in the morning and you have a stomach ache. What wonder what the heck is going on. You can’t get off the toilet or your head out of a bucket. You need to figure this out. What do you do? You use the Scientific Method!

Scientific Method 1. Observations – Observe your surroundings.

Scientific Method 2. Formulate a question – What do you want to know?

Scientific Method 3. Research and collect data – What do you already know about your question?

Scientific Method 4. Form a hypothesis – Propose an answer to your question based on observations, research, and data.

Scientific Method 5. Test hypothesis – run a series of experiments

Scientific Method 6. Observations – What do you see?

Scientific Method 7. Draw a conclusion – Did the results support your hypothesis? If not, modify the hypothesis based on observations.

The Scientific Method 1. State the Problem 2. What was the hypothesis? The Strange Case of BeriBeri In 1887 a strange nerve disease attacked the people in the Dutch East Indies. The disease was beriberi. Symptoms of the disease included weakness and loss of appetite, victims often died of heart failure. Scientists thought the disease might be caused by bacteria. They injected chickens with bacteria from the blood of patients with beriberi. The injected chickens became sick. However, so did a group of chickens that were not injected with bacteria. One of the scientists, Dr. Eijkman, noticed something. Before the experiment, all the chickens had eaten whole-grain rice, but during the experiment, the chickens were fed polished rice. Dr. Eijkman researched this interesting case. he found that polished rice lacked thiamine, a vitamin necessary for good health. 1. State the Problem 2. What was the hypothesis? 3. How was the hypothesis tested? 4. Should the hypothesis be supported or rejected based on the experiment? 5. What should be the new hypothesis? 15

Experiments Any experiment must have one control and one variable in order to be valid. Variable – Factor that changes in the experiment Control – Factor that does not change in an experiment

Variables: Independent Variable – What can be controlled. The part of the experiment you are changing Dependent Variable – Outcome of the experiment – What happened when the independent variable was changed or introduced.

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Independent Variable Independent Variable – the part that changes in order to do your experiment 20

Dependant Variable Dependent variable - what changes when the independent variable changes Dependent variable depends on the outcome of the independent variable. 21

Control Group Control Group Group that is untreated Compared to group that was treated 22

For Example…. You have two groups of plants growing in your house. You want your plants to grow large. You do some research and think that the amount of light will make your plants grow. One group of plant is in your kitchen and it gets 4 hours of sunlight every day. You take the other group of plants outside so that they can get more light. This group now gets 9 hours of light. In a week, the plants outside grew to be 2 feet tall. The plants in the kitchen grew to 1 foot tall. Questions: 1. What is the hypothesis? 2. What is the independent variable? The thing that changes in the experiment that you control. 3. What is the dependant variable? The thing that changes in the experiment that changed when the independent variable changed? 4. What is the control group? 23

Practice Sheet! 24

Units of Measurements Scientists came up with a system of measuring that all scientists around the world could use. SI – International System of Units

The SI system is easy to use because it is based on multiples of ten.

Metric Conversions: Kilo = 1000 Hecto = 100 Deca = 10 Base (Gram, Liter, Meter, Etc..) = 1 Deci = 1/10 (0.10) Centi = 1/100 (0.01) Milli = 1/1000 (0.001)

Measuring Distance The SI base unit of length is the meter, m. The size of the unit you measure with will depend on the size of the object being measured.

Measuring Volume The amount of space occupied by an object is called its volume. Liters or m3 V = L * W * H (for a box) L = length W = width H = height

Measuring Matter Mass is a measurement of the quantity of matter in an object. Grams

Measuring Weight Weight is a measure of the gravitational force exerted on an object. Newtons

Base Measurements: Length – Meter (m) - (39 inches) Mass – Grams (g) – Amount of matter in an object – It does not change!!!! (1 Paper Clip) Weight – Newtons (N) – Force of the pull of gravity on an object (changeable) Volume – Liter (L) or cm³ – A measure of the area of matter displaced by an object

Organizing Data: Tables Graphs: Line Graph – Used to show continuous change Bar Graph – Used to compare items Pie Charts – Used to show parts of a whole (ratio)

The horizontal axis, (x-axis), measures time.

Independent variable measured on x-axis. Dependent variable measured on or y-axis.

Graphs

Line Graph Line graphs often show how a relationship between variables changes over time.

Bar Graph A bar graph is useful for comparing information collected by counting.

Pie Graph A circle graph, or pie graph, is used to show how some fixed quantity is broken down into parts.

Scientific Notation: Used to express very large or very small numbers in multiples of 10 Rules: Numbers should between 1.0 and 9.9 X 10³ - Shows the number of places you moved the decimal Multiplication – Add Exponents Division – Subtract Exponents

1E4 = 104 = 10,000 1E3 = 103 = 1,000 1E2 = 102 = 100 1E1 = 101 = 10 1E0 = 10 0 = 1 1E-1 = 10 -1 = 0.1 1E -2 = 10-2 = 0.01 1E-3 = 10-3 = 0.001

Precision: Precision – The exactness of the measurement Accuracy – Describe how close a measurement is to the true value of the quantity measured

Accuracy vs. Precision