1. Measurement
in Science

2. Customary Units vs. Metric Units
DISTANCE
Inches, Feet,
Yards, Miles
Meters
LIQUIDS
Cups,Pints,
Quarts, Gallons
Liters
WEIGHT/ MASS
Ounces, Pounds,
Tons
Grams
TEMPERATURE
° Fahrenheit
° Celsius

3. Why are measurement standards important?
What is a standard?
It is an exact quantity that people agree to use for comparison.
Why are measurement standards important?
A meter in the U.S. is the same as a meter in France.

4. SI Units are... International Standards Abbreviated SI from the French
Le Systeme Internationale d’Unites or the
Common Name of the Metric System

5. Can you think about any situations that we use the Metric System in our everyday life – either home or at school?
Name at least 3 examples: 1. 2. 3.
Come on brain!!

6. Pros & Cons of Metric System
Why should we use this system?
Pro’s
Easy: based on the use of ten
Conversions are easier - Just move decimal point
Used all over the world – not just USA
Con’s
History of conflict all over the world
People don’t want to change
Replacement cost of machinery too high

7. What do all those prefixes mean?
International Standard Units (SI)

8. Putting It All Together
prefix
symbol
unit
centi- c m
meter
(0.01)
hundredth of a meter
milli- L m
liter
(.001)
thousandth of a liter
kilo- k g
gram
(1000)
thousand grams

9. King Henry dances merrily down center main.
How can I remember the order?
From LARGEST to smallest the easiest way to remember the prefixes is in a sentence……..
King Henry dances merrily down center main.
Or..
King Henry doesn’t milk dairy cows on Mondays.
Kilo- Hecto- Deka- BASE deci centi- milli-
Meter, Liter, Grams

10. Metric Conversions
Step 1: Locate the DECIMAL POINT in the number that you need to convert.
g = _________ cg
Decimal Point
Step 2: Mark the starting point (where the decimal point is in the original number) on the guide.
Kilo- Hecto- Deka- BASE deci centi- milli- .

11. This is the direction the
Step 3: Mark the ending point (where the decimal point is in the final number) on the guide with an X.
Kilo- Hecto- Deka- BASE deci centi- milli- . X
This is the direction the
DECIMAL will move.
g = _________ cg

12. . 2702.5 27.025 g = _________ cg 27.025 g = _________ cg
Step 4: Move the decimal point (.) in the direction of the X Stop moving the decimal when you reach the X That’s how many places you need to move the decimal point in the original number. .
Kilo- Hecto- Deka- BASE deci centi- milli- X
g = _________ cg
g = _________ cg
2702.5

13. SI Units for Measurement Used in Science
Length / Distance
Metric ruler:
Measured in meters (m)
Volume
Regular Shape – Length X Width X Height
Measured in cm3
Example: box, land, table tops
Metric ruler:
Irregular Shape – Displacement Method
Final Reading – Initial Reading = Volume
Measured in milliliters (mL)
Example: Liquids, rocks, marbles
Graduated cylinder:

14. Continued - SI Units for Measurement Used in Science
Mass
Balance:
Measured in grams (g)
Temperature
Thermometer:
Measured in degrees Celsius (OC)
Time
Clock:
Measured in seconds (s)

15. Density …the amount of mass in a given volume
Formula to calculate Density:
Units are expressed as:
- g/mL – density of a liquid
- g/cm3 – density of a solid
Mass
Volume
Density = D M V

16. Using a Ruler
When measuring an object with a ruler, never start at the “0” mark.
Rulers are less accurate due to wear and tear at the ends.
Begin at the 2, 4, 5 or 6 cm mark in order to get the most accurate mark. 5 6
What is the length of the red line? 6.2 cm or 1.2 cm
The red line would be 1.2 cm because the “5” is the starting point.
6.2 – 5 cm = 1.2 cm

17. Reading the Meniscus
When measuring liquid volume in a graduated cylinder, a meniscus often forms where the liquid ends.
graduated cylinders
In order to read this liquid volume, you must be at “eye-level” to the level of the liquid.
You take the reading at the BOTTOM of the meniscus.
The liquid level is 36.5 mL.

18. Read these liquid volumes in mL:B.
76.0 mL
11.5 mL