1. HB 1.A.4 through HB 1.A.8

2. Precision and Accuracy
Precision- measure of the degree to which measurements made in the same way agree with one another.
How repeatable are your measurements. The more repeatable, the more precise.
Accuracy- of a result is the degree to which the experimental value agrees with the true or accepted value
How close a measurement is to an actual or accepted value. The closer it is to the accepted or actual value, the more accurate.

3. What this means for an experiment
High degree of precision but poor accuracy
Means the same error is involved in repeated trials of an experiment.
High degree of accuracy and poor precision
Means the measurements reached the accepted value once but it was not repeated.
You should try to be accurate and precise in every experiment
But it is impossible to be completely accurate using the naked eye.
The more decimals in the recorded measurement, the greater the precision of the instrument.
An instrument read to the hundredths place is more precise than an instrument that reads to the tenths place.
The last digit read should be estimated on any piece of equipment.

4. Graphing Why do it? Steps to graph Organize data
Provide an easy way to explain data without the person reading the report.
Steps to graph
Make a table
Independent variable on the left and dependent variable on the right
Graph the organized data
Independent variable on the “X” axis and dependent variable on the “Y” axis.
Choose scales for X and Y axis
2 data points more than is needed on the vertical
Horizontal should be long enough for all data points to fit
Intervals should be in equal increments
Label each axis with name of the variable and units of measure
Title the graph

5. Examples of Graphs

6. What graph should I use?
Different relationships between different independent and dependent variables mean you should use different graphs.
But how do you know which one to use?
Line graph use with data that is collected all at the same time. Ex. Any variable over time
Bar graph use with data collected with different categories.
Circle graph use with data that shows a relationship to parts of a whole. Ex. percentage

7. Stepping Up to SI
In SI different units measure different things just like in English measurements
Meters = length Seconds = time
Liters = volume Kelvin = heat
Gram = mass Ohms =current
The ones above are base units. We add a prefix to the base to make the base unit smaller or bigger. The prefixes you need to know are:
Kilo- =1000 B Deci- = .1
Hecto- = 100 A Centi- = .01
Deka- = 10 S Milli- = .001 E

8. Stepping Up to SI
There are two ways to convert from one to the other. Both are fairly easy since they are all in increments of 10.
Conversion factors
Stairsteps

9. Metric Stairs
Start at the step your unit is on and move the number of steps to get to the unit you are changing to.
For every stair you move up move the decimal point to the left.
For every stair you move down move the decimal point to the right.

10. Science and Technology
Science is a process of inquiry that searches for relationships that explain and predict things in our world.
Technology is the application of scientific discoveries to meet needs and goals of humans through the development of products and processes
Science affects technology
Science is applied to technology to make products and processes that meet the needs of mankind
In science the scientific method is used
In technology the technological design process is:
Identify need or problem
Solution designed to meet it
Product is developed and tested
Results analyzed to determine how well it solved the problem

11. Comparison of Science and Technology