Introduction to Science Physical Science

The goal of science is to understand the natural world we live in. Why Science?? The goal of science is to understand the natural world we live in. Scientist hypothesize in order to try to explain what they think will happen in a certain situation

Steps of the Scientific Method Ask a question​ Form a hypothesis​ Design an Experiment​ Record data and analyze results​ Make a Conclusion

Designing an Experiment INDEPENDENT VARIABLE The factor you change on purpose Example: The size of the engine. The amount of fertilizer on plants. There can only be ONE independent variable DEPENDENT VARIABLE The result of what you changed The speed of the car. Growth rate of the plants.

What are we testing here?

CONSTANTS Factors (variables) you try to keep the same to make the comparison “fair” Example: Test the speed of the car on the same track with the same car. Same amount of water & light for the plants

CONTROL GROUP An experiment where one group receives no treatment. This group is used for comparison. Example: Speed of a car that did not get a larger engine. Growth rate of a plant that did not get any fertilizer. EXPERIMENTAL GROUP The group that has had the independent variable added to it. The car with the bigger engine. Growth rate of a plant that did receive fertilizer.

Scientists ALWAYS confirm results REPEATED TRIALS Repeat the experiment to increase confidence in your results.

Metric System Scientists use a standard unit of measurement called the International System of Measurement (SI) The metric system is a different way of measuring things. The practice is the same, but different units are involved.

Measurement ​ Units used​ length ​ meter (m)​ volume ​ liter (L)​ mass ​ kilogram (kg) ​ force ​ Newton (N)​ temperature ​ Degrees Celsius (oC) ​ or Kelvin (K)​ time ​ seconds (s)​ work ​ Joules (J)​ power ​ Watts (W)​ Energy​

Metric System Every measurement will include one of the base words. The metric system uses Prefixes too. Every prefix is related to the base units. But how is that possible…

Metric System The prefixes for large measurements…. KILO (k) 1 kilometer = 1000 meters HECTO (h) 1 Hectoliter = 100 liters DECA (da) 1 Decagram = 10 grams

Metric System The small measurements… DECI (d) – 1 decimeter = 1/10 meter CENTI (c) – 1 centiliter = 1/100 liter MILLI (m) – 1 milligram = 1/1000 gram

King Henry Died by Drinking Chocolate Milk Kilo Hecto Deca Base Deci Centi Milli

When you are converting from one unit to another unit First figure out what you are starting with Then where (which direction) you are going! If you move to the right (aka big to small) then you move the decimal to the right. If you move to the left (aka small to big) then you move the decimal to the left.

Try this one. 1 meter = ______ hectometer 1st- Figure out your starting point and where you are going! K h da b d c m 2nd – Find the Decimal and move it the same way and number you moved in step 1.

And this one. 2.5 kilograms = ______ grams 1st- Figure out your starting point and where you are going! K h da b d c m 2nd – Find the Decimal and move it the same way and number you moved in step 1.

K h da b d c m Last one! 17.504 deciliters = ______ decaliters 1st- Figure out your starting point and where you are going! K h da b d c m 2nd – Find the Decimal and move it the same way and number you moved in step 1.

Graphing in Science Graphs help show data quickly and efficiently. Graphs can show trends in the data Common Graphs of Science Data Bar Graphs Circle Graphs Line Graphs (We will use line graphs for nearly every graph this year!)

Label the axes Create a scale Plot the data Draw a line Add a title Graphing Procedure Label the axes Independent Variable on X-Axis Dependent Variable on Y-Axis Create a scale Consistent Points (go up by the same amount) Scales can be different for x-axis and y-axis Plot the data Draw a line Add a title

Types of Trends Positive Linear Trend When one variable increases The other variable increases Negative Linear Trend The other variable decreases

Types of Trends Positive Non-Linear Trend When one variable increases The other variable increases Changing Non-Linear Trend What’s going on here?

No Trend Can be used to determine that the variables do not really have any cause/effect relationship. May be affected by something not being tested