Systems of Measurement
Introduction
- Every measurement consists of:
Types of Measurement Systems
- English System (Used in the US)
- Volume: gallons
- Mass: pounds
- Metric System (Used in medicine and science)
- Base units:
- Length: meters
- Mass: grams
- Volume: liters
- Time: seconds
- SI System (International System)
- Based on the metric system
Metric System Prefixes
- Larger Prefixes:
- Tera (T)
- Giga (G)
- Mega (M)
- Kilo (k)
- Smaller Prefixes:
- Decimeter (d)
- Centimeter (c)
- Millimeter (m)
- Micrometer (µ)
- Nanometer (n)
- Picometer (p)
Conversion in Metric System
- Move the decimal to convert between units:
- Moving left: decimal moves left
- Moving right: decimal moves right
- Examples:
- 1 gram to hectograms: move 2 spots left
- 254 centiliters to kiloliters: move 5 spots left
- 7.89 millimeters to nanometers: move 6 spots right
English System
- Length:
- 1 foot = 12 inches
- 1 yard = 3 feet
- 1 mile = 5,280 feet
- Mass:
- Volume:
- 1 gallon = 4 quarts
- 1 quart = 2 pints
Volume Measurement
- Glassware:
- Flask
- Graduated cylinder
- Syringe
- Pipette
- Volume Displacement:
- Use for irregularly shaped objects
- Calculate by: V_final - V_initial = Volume of the object
Practical Examples
- Volume of a Cube:
- For a cube with sides of 2 cm, the volume is:
- 2 cm x 2 cm x 2 cm = 8 cubic cm
- Equivalent to 8 milliliters
Identifying Measurement Systems
- Examples:
- Micrometer: Metric, Length
- Gallons: English, Volume
- Kilogram: Metric, Mass
- Cubic centimeter: Metric, Volume
- Pound: English, Mass
- Milliliter: Metric, Volume
Conversions
- Microgram to Gram:
- 1 gram = 10^6 micrograms
- 1 microgram = 10^-6 grams
- Encourage use of scientific notation for clarity.
This lecture covers the basics of measurement systems, their units, and conversions between different units, highlighting both the metric and English systems.