Bell Ringer

1
Bell Ringer

• You choose the number..
• Why do I require you to put on lab aprons or
  goggles for certain experiments?
• When is your vocabulary due? And its quiz?

2

• SCIENTIFIC METHOD
• Organized set of procedures scientists use to
  investigate nature and problems.
• Begins by observing a problem or seeing a trend
  in scientific data that can be investigated.
• Whatever problem you start out with must be
  TESTABLE!!
• Ex A scientists notices that obese mice seem to
  have a higher rate of cancer.
• Could he test this observation?

3
Scientific Method
4
Scientific Method
PROBLEM
Observe
Hypothesis
Experiment
Analyze
Conclude
Support Hypothesis
Not supported
5
What is a Hypothesis?

• An Educated guess or prediction based on
  observations
• It MUST be TESTABLE
• if you cannot test it, then it is not a
  hypothesis
• You never really PROVE your hypothesis
• You data either supports it, or it is not
  supported

6
Experimenting

• Variables may have more than a single value, or
  may change
• Independent variable the variable that is
  changed by the person doing the experiment
• Dependent variable changes according to other
  variables changing in the experiment
• (Cause Effect) Independent Cause, Dependent
  Effect

7
Experimenting

• To make sure we are only testing one variable at
  a time we have to have a
• Control standard to compare results
• And a.
• Constant something that is NOT changed

8
Applying it

• A farmer wanted to test different types of
  fertilizer to see how well each helped plants to
  grow. He set up four pea plants. Each was given
  the same amount of sunlight, water, and kept at
  the same temperature. Three plants were given
  different types of fertilizer. The fourth plant
  was not given any fertilizer at all. Every two
  days the farmer will measure the growth of his
  plants.

9
What was what?

• Independent variable?
• Fertilizer
• Dependent variable?
• Plant growth
• Constant(s)?
• Plant type, water, sunlight, temp.
• Control?
• The plant that received no fertilizer.

10
What happens after a hypothesis is supported?

• It becomes a Theory.
• Theory is a hypothesis found to be true or
  supported over and over again through
  experimentation
• Scientific Law something that is found to be
  supported through nature all the time.
• A theory becomes a Law if it is never disproved
  and found to ALWAYS be true!!

11
Line Graphs

• Horizontal axis x axis
• Vertical axis y axis
• Independent variable
• goes on the Horizontal axis
• HIV horizontal independent variable

http//www.bbc.co.uk/schools/ks3bitesize/maths/alg
ebra/images/co_ord1.gif
12
Bar Graphs

• Good for comparing information gathered by
  counting
• Can use to show cost comparisons, ect.

http//education.yahoo.com/homework_help/math_help
/solutionimages/minialg1gt/11/1/1/minialg1gt_11_1_
1_6_100/f-bargraph2.gif
13
Pie Charts or Circle Graphs

• Shows a whole broken
• into parts
• Break parts into percentages
• Ex. 18 out of 20 is 18/20 90

http//www.geography.hunter.cuny.edu/tbw/wc.notes
/14.climate.change/US.energy.consumption.pie.chart
.jpg
14
Which graph?

• Which graph would you use to show change in
  temperature for January?
• Line graph
• Which graph would you use to show data from a
  survey you collect showing what percentage of
  students play each sport?
• Circle would be best
• What graph would best represent different costs
  of cars?
• Bar graph

15
Data Relationships

• Inverse Relationship
• One data point decreases as the other increases
  

16
Data Relationships

• DIRECT relationship
• As one increase, so does the other or vice versa
  

17
SI (System International) or Metric System

• Standard Measurement System used for Science and
  around the world.

18
SI (Metric) Bases Prefixes

• Metric Bases
• Length----Meter (m)
• Mass----Gram (g) (kilogram)
• Temperature-----Kelvin (K)
• Volume-------Liter (L)

• Common Prefixes
• Kilo (k) 1,000
• Deci (d) .1
• Centi (c) .01
• Milli (m) .001
• Nano (n) 10-9

19
Dimensional Analysis Conversion Factors or
Units

• Used to change from one unit to another
• Ex How many kilograms are in 1,500 grams
• 1 kilogram 1,000 grams conversion unit
• Using this
• 1500 grams x 1 kilogram 1500
• 1000 grams 1000
• 1.5 kilograms

20
Easier Converting

• Rule
• Kilo hecto Deca Base Deci Centi Milli
• K h dk B d c m
• Ex. How many centimeters are in 100 millimeters.
• Using the rule, move your decimal the same amount
  of spaces and the same DIRECTION.
• Starting at milli, move 1 place to the left!!
• So there are 10 cenitmeters in 100 millimeters

100
21
Metric Conversion Practice

• How many grams are in 2 kilograms?
• How many decimeters are in 20 centimeters?
• How milliliters are in 2 liters?

22
Temperature

• Science ONLY uses
• Celsius Kelvin
• Kelvin ABSOLUTE temperature scale
• 0 Kelvin is the COLDEST possible temperature
• 0 Kelvin ABSOLUTE ZERO
• K oC 273
• oC K - 273

23
Volume

• Volume length x width x height
• V l x w x h
• Units will be cubed Ex. cm3
• For Liquids
• 1mL 1cm3
• Using this conversion, How many cm3 are in 2
  liters?

24

• Mass quantity of matter a substance contains
• Weight pull of gravity on a substance
• Your weight would change if you went to another
  planet, Mass would NOT.
• Density Mass per unit volume g/cm3
• Derived Unit unit that is found by combining
  other SI units
• Density of Water is 1.0 g/cm3

25
More or less dense than water?

• If water is 1 then..
• Sinking MORE dense than water
• Density greater than 1
• Floating LESS dense than water
• Density is less than 1

26
Measurement, precision, and accuracy

• Precision compares how close measurements are
  to each other
• REPEATABILITY
• Accuracy relates to how close the measurements
  are to the real or accepted value
• ON THE BULLS EYE

27
Measurement, precision, and accuracy
Precise, but not accurate
28
Measurement, precision, and accuracy
Accurate, but not precise
29
Measurement, precision, and accuracy
Accurate AND precise
30
After the Quiz

• Work on either
• Hwk Metric mania (Checked Monday)
• Section Reviews
• Vocabulary (due Tuesday)
• You will have a quiz over all material covered on
  Wednesday 1-28.
• Your first test (Bio. Intro) and notebook check
  two will be Friday 1-30.