1. T. Trimpe 2008 http://sciencespot.net/
Lesson 1: Length
T. Trimpe

2. The Metric System Easier to use because it is a decimal system
Every conversion is by some power of 10.
A metric unit has two parts
A prefix and a base unit.
prefix tells you how many times to divide or multiply by 10.

3. SI Prefixes – Page 74 Common to Science
Unit Abbreviation
Meaning
Exponent
Kilo- k
thousand
103
Deci- d
tenth
10-1
Centi- c
hundredth
10-2
Milli- m
thousandth
10-3
Micro- 
millionth
10-6
Nano- n
billionth
10-9

4. The Metric System : A measurement system based on the powers of ten.
Copyright © 2010 Ryan P. Murphy

5. The Metric System : A measurement system based on the powers of ten.
Copyright © 2010 Ryan P. Murphy

6. The Metric System : A measurement system based on the powers of ten.
Large
Copyright © 2010 Ryan P. Murphy

7. The Metric System : A measurement system based on the powers of ten.
Large
Copyright © 2010 Ryan P. Murphy

8. The Metric System : A measurement system based on the powers of ten.
Copyright © 2010 Ryan P. Murphy

9. The Metric System : A measurement system based on the powers of ten.
Copyright © 2010 Ryan P. Murphy

10. Length
In SI, the basic unit of length is the meter (m)
Length is the distance between two objects – measured with ruler
We make use of prefixes for units larger or smaller

11. English vs. Metric Units
Which is longer?
A. 1 mile or 1 kilometer
B. 1 yard or 1 meter
C. 1 inch or 1 centimeter
1.6 kilometers
1 mile
1 yard = meters
1 inch = 2.54 centimeters
Left Image: Right Image:

12. Click the image to watch a short video about the meter.
Metric Units km m cm mm
The basic unit of length in the metric system in the meter and is represented by a lowercase m.
Standard: The distance traveled by light in absolute vacuum in 1⁄299,792,458 of a second.
Metric Units
1 Kilometer (km) = 1000 meters
1 Meter = 100 Centimeters (cm)
1 Meter = 1000 Millimeters (mm)
Click the image to watch a short video about the meter.
Which is larger?
A. 1 meter or 105 centimeters
B. 4 kilometers or 4400 meters
C. 12 centimeters or 102 millimeters
D millimeters or 1 meter

13. Measuring Length How many millimeters are in 1 centimeter?
1 centimeter = 10 millimeters
How many millimeters are in 1 centimeter?
What is the length of the line in centimeters? _______cm
What is the length of the line in millimeters? _______mm
What is the length of the line to the nearest centimeter? ________cm
HINT: Round to the nearest centimeter – no decimals.
Ruler: