t he n ature of s cience measurement. sn#3 w hat is m easurement in s cience ? measurement using...
TRANSCRIPT
THE NATURE OF SCIENCE
Measurement
SN#3WHAT IS MEASUREMENT IN SCIENCE?
Measurement using scientific tools is important because scientific tools are objective-while our own senses are subjective. There are several physical properties which are measured using specific scientific tools.
Mass-how much matter an object. Tool = balance; unit is grams
Weight – measure of gravitational pull on an object. Tool = scale; unit is Newtons N
Volume: How much space an object takes up. Tool = graduated cylinder; unit cm3 = ml
Temperature: average kinetic energy measured with a thermometers; unit C centigrade
Density: how much mass per volume is present. This is measured by dividing the mass by the volume. The unit for density is g/ml or g/ml.
Distance – how far apart items are measured with a metric ruler; unit meters
Accuracy- How close you are to the actual measurement
Precision – How exact and consistent the measurement is.
Left Hand Assignment: page 8
Over/Under Estimate yourself1. Draw a table like the one on the board on page 8.2. Copy items listed below in the first column.3. * Mass – Highlighter * Length – your arm
* Volume – Box * Length - foot* Volume – in the cup * Height – Lab Counter* Temp – room * Height - Door* Width – Door * Height - You* Mass – 4 pieces of * Temp – water in fish Laffy Taffy tank
4. Estimate the measurement of the item in the 2nd column. Make sure you use the proper unit of measure (cm, ml, cm , C, g)
5. Accurately measure the items you just gave an estimate for in the third column of the chart.
6. Calculate the difference between your estimate and the actual measurement in the 4th column.
Item Est. Meas. Diff.M-Highlighter
V-in cup
V- Box
T- Room
W-Door
M-4 laffy taffy
L-Arm
L-Foot
H-Lab Count.
H-Door
H-You
T-Fish Tank
THE NATURE OF SCIENCE
Scientific Process
SN#4 WHAT IS THE SCIENTIFIC
PROCESS?
The scientific process is a way to make and answer scientific questions by making observations and doing experiments.
STEPS IN THE SCIENTIFIC PROCESS:
Observation: gather information about an event through the senses and scientific tools. These lead to scientific questions.
Questions: Problem, Questions in science are not answered yes or no.
Hypothesis: A testable possible solution to a scientific question.
Material & Procedures: What is needed to do the experiment and the directions for the experiment
Results: Data Data Collection (Data Table) Data Display (Graph usually a line graph)
Analysis: Explains the data display Conclusion: Communicate the results in terms of the
hypothesis
Left Hand Assignment: page 10Draw an illustrate picture of the steps in the scientific process.
SN#5 WHAT ARE SCIENTIFIC OBSERVATIONS, QUESTIONS, AND
HYPOTHESES?
Observation: An observation is a gathered through the senses and scientific tools – observations lead to scientific questions.
TWO TYPES OF OBSERVATIONS
(No Notes)
Qualitative
Descriptions of sights, sounds, smells, and texturesEx. – round, smooth, rough, green, pleasant smell
Quantitative
Descriptions that are expressed in numbersEx. – expressions of time, temperature, distance, mass, and volume
MAKING AN INFERENCE
An inference is a statement or conclusion that is made from observations of something.
We make inferences all the time, and you’d be surprised to know that you are pretty good at it.
Mr. Fishy
Write 2 observations about Mr. Fishy on pg 12
Questions: A question in science asks about the relationship between events; and are not answered yes or no.
Mr. Fishy
Write 2 questions based on your observations about Mr. Fishy on pg 12
Hypothesis – A testable possible solution to a scientific question. We will use the “if…then…” format to write the hypothesis. Hypotheses must be written in scientific language. Do not use personal pronouns.
Change: My hypothesis to The hypothesis
Lead To
Inferences Hypotheses
The “guesses” you have about the cause of something (inferences) lead to the possible explanations about why it happened (hypotheses).
ALWAYS write a hypothesis using this method …
IF … then …
If I study for my Science quiz, then I should make a good grade
Writing a GOOD Hypothesis(no notes)
QUESTION:
HOW DOES FERTILIZER AFFECT TOMATO PLANT GROWTH?
Hypothesis: If fertilizer is used then the plant will produce more tomatoes.
QUESTION:
HOW DOES VITAMIN C HELP PREVENT COLDS?
If you take vitamin C then you will make it through the day and won’t get sick.
HYPOTHESIS
Question:
Which produces higher grades on science tests, studying with music on, or studying with quiet conditions?
HYPOTHESIS
If I study quietly then I will get a higher grade on my test.
Mr. Fishy
Write a hypothesis about Mr. Fishy on page 12
SN#6 Materials, Procedures, Experiments.
Materials: Specific list of materials needed to conduct an investigation; must give the number of items needed as well as the type.
Example: Two 50ml graduated cylinder Procedures: Numbered list of directions
for an investigation must start with a verb.gather materialsmeasure 50 grams of salt
ExperimentA procedure
to test the hypothesis.
Variable – factor in the
experiment that is being tested
A good or “valid”
experiment will only
have ONE variable!
Scientific Experiments Follow Rules
An experimenter changes one factor and observes or measures what happens.
SN#7 Variables, Results, Data
Glue down note page on pg 17
The Control VariableThe experimenter makes a special effort to keep other factors constant so that they will not effect the outcome.
Those factors are called control variables.
What is the Purpose of a Control?
Controls are variables that DO NOT being tested or receiving experimental treatment.
Controls are used for COMPARISON
Constants are the factors that are kept the same.
Other Variables
The factor that is changed is known as the independent variable.
The factor that is measured or observed is called the dependent variable.
IDENTIFYING VARIABLES
There are 3 types of variables:
Independent Variable (Changed)
Dependent Variable (Measured)
Control
IV VS. DV(No Notes)
Independent variable Also called the
manipulated variable What YOU control and
change during an experiment
X-axis Comes after the word
if in the hypothesis
Dependent Variable Also called the
responding variable Changes because of
the IV What you measure in
an experiment Y-axis Comes after they
word then in the hypothesis
Example of Controls & Variables
For example, suppose you want to figure out the fastest route to walk home from school.
You will try several different routes and time how long it takes you to get home by each one.
Since you are only interested in finding a route that is fastest for you, you will do the walking yourself.
What are the Variables in Your Experiment?
Varying the route is the independent variable
The time it takes is the dependent variable
Keeping the same walker throughout makes the walker a control variable.
One more thing… it is best to make several trials with each independent variable.
ResultsIn the scientific
process, data is recorded and kept in the data table.
Data from the data table is then displayed in a graph.
SN#8 HOW IS DATA DISPLAYED?PG 19
Graphs are used to visually represent data.
Bar Graphs are used for comparison Line graphs show relationships between
variables. When in doubt use a line graph.
All graphs must be labeled – Bar and line graphs must be labeled with
Title Independent variable on x-axis Dependent variable on y-axis
**USE THIS TO HELP YOU REMEMBER WHERE TO PLACE THE DIFFERENT TYPES OF VARIABLES AND DATA.
Days Survived Without Water in Different Light
0
5
10
15
20
25
30
35
40
45
50
Green Red Blue White Sunlight No Light(Control)
Type of Light
Day
s S
urv
ived
Identify the Variables:
Independent:
_________________
Dependent:
_________________
Control:
__________________
Identify the Variables:
Independent:
Type of Light
Dependent:
# of Days the Plant
Survived
Control:
The “no light” condition
Days Survived Without Water in Different Light
0
5
10
15
20
25
30
35
40
45
50
Green Red Blue White Sunlight No Light(Control)
Type of Light
Day
s S
urv
ived
LINE GRAPH VS. BAR GRAPH
Average Monthly Temperature in Savannah, Georgia
0
10
20
30
40
50
60
70
80
90
100
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
Tem
pera
ture
(Fah
renh
eit)
Miles Hiked Per Day
0
2
4
6
8
10
12
14
16
Day 1 Day 2 Day 3 Day 4 Day 5 Day 6
Day of Trip
Num
ber
of M
iles
Continuous data Categorical data
Left Hand Assignment: page 14 Mr. Fishy Materials: Mr. Fishy, 10 subjects, mood
definitions Procedures: Remove Mr. Fishy from the sleeve Ask subjects to select a mood from the list of
mood definitions Place Mr. Fishy on the subject’s palm Read Mood Record Mood
Mr. Fishy IV: Subject DV accuracy of mood reading Control: none Constent: Mr. Fishy list of
moods Qualitative data: mood Quantitative data: Percent accurate
Glue down Data table Glue Down Mr. Fishy’s Moods Pg. 16 (you are number 1)
Left hand assignment pg 18
SN# 9HOW ARE ANALYSES AND CONCLUSIONS
WRITTEN?
Get handout and glue it down on page 21 of your notebook.
An Analysis is and EXPLANATION of the graph.
Do not start your conclusion with the words IN CONCLUSION!!!!!!!!!!!!!!!Conclusions should be at least 4 sentences long.
Left Hand Assignment: page 20
1. Make a data table on a separate sheet of paper for your Mr. Fishy lab. We will glue this in later.
2. Write an Analysis for your Mr. Fishy Lab3. Write a Conclusion for your Mr. Fishy
Lab.