Ms. Moore 8/17/12 Albert Einstein physicist Stephen Hawking cosmology and quantum gravity

Scientists are… Scientist: a person who is studying or has expert knowledge of one or more of the natural or physical sciences Who are your favorite scientists? How many scientists are in this room?

What is Science? Science: organized way of using evidence to learn about the natural world The goal of science is to investigate and understand the natural world, to explain events in the natural world, and to use those explanations to make useful predictions. Major categories of science: Life science Earth science Physical science

Thinking Like a Scientist The Scientific Method: organized set of investigation Ask a Question/Research Form a Hypothesis Test Hypothesis/Design Experiment Record/Analyze Data Draw Conclusions/Report Findings

Ask a Question/Research Many scientific investigations begin when someone observes an event in nature and wonders why or how it occurs. Next, a question is proposed. These questions lead to the investigator researching the subject and learning information about it.

Form a Hypothesis Hypothesis: a possible explanation for a problem using what you know and what you observe. A hypothesis: Made before data is gathered Possible answer to your question

Hypothesis: Activity Watch “The Battle at Kruger” and make a hypothesis.The Battle at Kruger Will your hypothesis change as more data is gathered from watching the video?

Test Hypothesis/Design Experiment Test hypothesis: Observation: the process of gathering information about events or processes in a careful, orderly way Experiment: tests the effect of one thing on another using controlled conditions variables: value varies/subject to change Independent variable: value manipulated (ex. fertilizer) Dependent variable: value changes depending on response to independent variable (ex. growth) constants: a factor that does not change when other variables change (ex. sunlight, water, temperature, etc.) controls: standard by which the test results can be compared (ex. unfertilized plant) Models can represent an idea event, or object to help others understand

Record/Analyze Data Organize the results in easy-to-read tables, charts, and/or graphs How would you share the information you found with others? Is there a better way to answer the question?

Drawing Conclusions/Reporting Based on the analysis of your data, you are now ready to draw a conclusion: You decide whether or not your hypothesis is supported. If the data does not support the hypothesis it should probably be revised. Bias occurs when what the scientist expects changes how the results are viewed. Running many trials with a measurable result can lessen bias.

Replication The experiment must be repeatable. A scientific theory is an explanation of things or events based on knowledge gained from many observations and investigations. If scientists repeat an investigation and the results always support the hypothesis, the hypothesis c an be called a theory. Scientific law is a statement about what happens in nature and seems to be true all the time. Example: gravity—no experiments have been performed to disprove this accepted law of gravity

Limitations of Science Technology is the application of science to help others It is not always possible to do an experiment to test a hypothesis: Ethical issues of humans Ex: Does this chemical cause cancer in humans? Disruption of a natural system Ex: How do animals in the wild interact with each other?

Scientific Method Activity Students will work with lab groups to understand the scientific method. Each group must: Ask a question Form a hypothesis Design an experiment Including all variables that would be tested Create fictional data that accepts or rejects the hypothesis Draw conclusion

Standards of Measurements A standard is an exact quantity that people agree to use to compare measurements For a measurement to make sense, a number and unit must be present. International System of Units: in 1960s all scientists agreed upon an updated metric system; it is abbreviated SI

SI Base Units Quantity MeasuredUnitSymbol Used Lengthmeterm MasskilogramKg TimeSeconds Electric currentampereA TemperaturekelvinK Amount of substancemolemol Intensity of lightcandelaCd PrefixSymbolMultiplying Factor Kilo-k1,000 Deci-d.1 Centi-c.01 Milli-m0.001 Micro- µ Nano-n

Measuring Distance Length is the distance from one point to another What can we use to measure length in the lab? Common SI Units (meter = slightly longer than a yard) 1 meter (m) = 100 centimeters (cm) 1 meter = 1000 millimeters (mm) 1000 meters = 1 kilometer (km)

Measuring Matter The amount of matter in an object is defined as mass. How could we measure mass in lab? Common SI Units (1 gram = 1 paperclip) 1 kilogram (kg) = 1000 grams (g) 1 gram = 1000 milligrams (mg) 1000 kilograms = 1 metric ton (t)

Finding Volume Volume is the amount of space an object takes up. How is volume measured? Common SI Units 1 liter (L) = 1000 milliliters (mL) 1 liter = 1000 cubic centimeters (cm 3 ) Density is the mass per unit volume of material Mass (g)/ Volume (cm 3 )

Temperature Temperature is used to measure hotness or coldness. How is temperature measured? Common SI Units (Kelvin) Add 273 to the °C to determine K 0°C = freezing point of water 100°C = boiling point of water

Common English-Metric Conversions 2.54 centimeters (cm) = 1 inch (in.) 1 meter (m) = inches (in.) 1 kilometer (km) = 0.62 miles (mi) 1 liter (L) = 1.06 quarts (qt) 236 milliliters (mL) = 1 cup (c) 1 kilogram (kg) = 2.2 pounds (lb) 28.3 grams (g) = 1 ounce (oz) °C = 5/9 x (°F – 32)

Metric/SI Measurement Lab Using the knowledge we learned today, complete the worksheet using lab materials supplied at your table. Who has bigger hands: practice with the scientific method