1. Find the length of a paperclip with each of the three “rulers”
Ruler a
Ruler b
Ruler c
Were all of your measurements identical
Which measurement required the greatest degree of estimation
How do your measurements indicate the difference in degree of estimation>

2. Unit 1- Precision and Accuracy
Accurate- Measurements that are close to the “correct” value – Bull’s eye
Precise- Measurements that are close to each other.

3. Accuracy/Precision video
Uncertainty in measurement video

4. Measurements… actual= 2.4cm
Student A
Student B
Trial 1
2.5 cm
1.8cm
Trial 2
2.4 cm
1.7cm
Trial 3
2.3 cm
Average:
2.4cm
1.76cm
1. Were either of the students accurate? Which one? WHY?
2. Were either of the students precise? Which one? WHY?
3. Were either of the students both accurate and precise? Which one? WHY?

5. Uncertainty in measurement
When measuring this pin, its about 2.85.
The last # which you estimate is the ____________
In this case, the uncertain # is _______
Measurements are only as precise as the _________

6. Uncertainty in measurement
When measuring this pin, its about 2.85.
The last # which you estimate is the UNCERTAIN NUMBER
In this case, the uncertain # is 5
Measurements are only as precise as the device

7. Units Notes Units: the scale that goes with numbers
There are 3 systems:
English – in America (ex. Foot, pound)
Metric- EVERYWHERE (ex. Meter, gram)
SI – for science
Based on metric

8. The Fundamental SI base units
measurement
unit
abbreviation
instrument
picture

9. The Fundamental SI base units
measurement
Length
unit
meter
abbreviation m
instrument
ruler
Picture

10. The Fundamental SI base units
measurement
Length
mass
unit
meter
kilogram
abbreviation m kg
instrument
ruler
Balance
picture

11. The Fundamental SI base units
measurement
Length
mass
volume
unit
meter
kilogram
liter
abbreviation m kg l
instrument
ruler
Balance
Graduated cylinder
picture

12. The Fundamental SI base units
measurement
Length
mass
volume
temperature
unit
meter
kilogram
liter
Kelvin
abbreviation m kg l K
instrument
ruler
Balance
Graduated cylinder
thermometer
picture

13. The Fundamental SI base units
measurement
Length
mass
volume
temperature
time
unit
meter
kilogram
liter
Kelvin
second
abbreviation m kg l K s
instrument
ruler
Balance
Graduated cylinder
thermometer
stopwatch
picture

14. Mass Mass = quantity of matter in an object.
Weight= force exerted on an object by gravity.