SI System International System of Units Taking Measurements

Objective Determine volume, temperature, mass, and distance given pictures and measurements. Determine volume, temperature, mass, and distance given pictures and measurements. CLE 3202.Inq.3 Use appropriate tools and technology to collect precise and accurate data. CLE 3202.Inq.3 Use appropriate tools and technology to collect precise and accurate data.

SI System A decimal system of measurement whose units are based on standards and scaled on multiples of ___ A decimal system of measurement whose units are based on standards and scaled on multiples of ___ Based on units of 10 Based on units of 10 ten

SI System Helps us communicate with other countries Helps us communicate with other countries

Kilo (k) = 1000 Kilo (k) = 1000 Hecta (h) = 100 Hecta (h) = 100 Deka (D) = 10 Deka (D) = 10 Base = 1 Base = 1 Deci (d) = 0.1 Deci (d) = 0.1 Centi (c) = 0.01 Centi (c) = 0.01 Milli (m) = Milli (m) = SI System The system is easy to use because it is based on multiples of 10 1 meter = 100 cm1 kilogram = 1000 grams1 gram = 1000 milligrams1 liter = 1000 milliliters1 kilometer = 1000 meters1 centimeter = 10 millimeters

Measurement in Science Le Systeme International d’Unites (International System of Units) or SI Units

S.I. Base Units The International System of Units (S.I.) defines seven base units for the seven base quantities: Quantity Name Symbol lengthmeterm masskilogramkg timeseconds electric currentampereA thermodynamic temperaturekelvinK luminous intensitycandelacd amount of substancemolemol

S.I. Base Units

Unit = meter Unit = meter Symbol = m Symbol = m Tool of measurement= meter stick Tool of measurement= meter stick Length

Length The distance from one point to another The distance from one point to another Meter – the SI unit of length Meter – the SI unit of length Tool used to measure length depends on the size of the object Tool used to measure length depends on the size of the object Larger objects (i.e. the room) Larger objects (i.e. the room) – meter stick – meter stick Smaller objects (i.e. pencil length) Smaller objects (i.e. pencil length) – centimeter ruler – centimeter ruler Frequently used SI units Length 1 millimeter (mm) = 1000 micrometers (  m) 1 centimeter (cm) = 10 millimeters (mm) 1 meter (m) = 100 centimeters (cm) 1 kilometer (km) = 1000 meters (m) 1 light-year = 9,460,000,000,000 kilometers (km)

Measuring Length Measure the distance from Point A to B Measure the distance from Point A to B What distance is Point A? Point B? What distance is Point A? Point B? What is the total distance between points? What is the total distance between points? 4.5 cm6.4 cm 6.4 cm – 4.5 cm =1.9 cm

Definitions Mass = the amount of matter in something Mass = the amount of matter in something

Mass Unit = gram Unit = gram Symbol = g Symbol = g Tool = balance Tool = balance

Mass Mass is measured using a balance or triple beam balance Mass is measured using a balance or triple beam balance Or an electronic balance Or an electronic balance

Mass The SI unit for mass is the kilogram (kg) The SI unit for mass is the kilogram (kg) The gram is the base unit (g) The gram is the base unit (g) However, some measurements of mass like the mass of vitamins or medicines are so small that we use milligrams (mg) to measure their mass Frequently used SI units Mass 1 gram (g) = 1000 milligrams (mg) 1 kilogram (kg) = 1000 grams (g) 1 metric ton = 1000 kilograms (kg)

Measuring Mass Measured using a balance Measured using a balance What is the mass of this object? What is the mass of this object? 175 g

Definition Volume = the amount of space that something takes up Volume = the amount of space that something takes up

Volume Unit = liter, meter 3 Unit = liter, meter 3 Symbol = L, m 3 Symbol = L, m 3 Tool = graduated cylinder, meter stick Tool = graduated cylinder, meter stick

Volume Volume of a liquid is found using a graduated cylinder Volume of a liquid is found using a graduated cylinder Unit is liters (L) or milliliters (mL) Unit is liters (L) or milliliters (mL) Frequently used SI units Volume 1 milliliter (mL) = 1 cubic centimeter (cc) or (cm 3 ) 1 liter (L) = 1000 milliliters (mL) or 1 dm 3

Measuring Volume Liquid volume measured using graduated cylinder Liquid volume measured using graduated cylinder Read volume at meniscus ( downward curve of water) Read volume at meniscus ( downward curve of water) What is the volume of this liquid? What is the volume of this liquid? 45 mL 45 mL

Measuring Volume Find the volume of these liquids Find the volume of these liquids 16 mL15 mL 12.5 mL

Volume Volume of a solid is found using the volume equation Volume of a solid is found using the volume equation length x width x height length x width x height units for the volume of a solid are… units for the volume of a solid are… m x m x m = m 3 OR cm x cm x cm = cm 3 m x m x m = m 3 OR cm x cm x cm = cm 3 Also know that 1 mL = 1 cm 3 = 1 cc (cubic centimeter) Also know that 1 mL = 1 cm 3 = 1 cc (cubic centimeter)

Measuring Volume Solid volume measured using volume equation (l x w x h) Solid volume measured using volume equation (l x w x h) What is the volume of a cube that is 2 cm x 2 cm x 2 cm? Volume = l 1 x l 2 x l 3 = 2 cm x 2 cm x 2 cm Volume = 8 cubic centimeters (8 cm 3 )

Measuring Volume Calculate the volume of the box Calculate the volume of the box 5 mm 2 mm 6 mm Volume = 60 mm 3 6 mm X 5 mm X 2 mm l x w x h

Temperature The amount of heat in something The amount of heat in something Tool used to measure temperature is a thermometerTool used to measure temperature is a thermometer Celsius is the unit of measure in the SI system Celsius is the unit of measure in the SI system

Temperature Unit = Celsius Unit = Celsius Symbol = ºC Symbol = ºC Tool = Thermometer Tool = Thermometer

Temperature Unit = Kelvin Unit = Kelvin Symbol = K Symbol = K Tool = Thermometer Tool = Thermometer

Temperature SI unit for temperature is the Kelvin (K) SI unit for temperature is the Kelvin (K) Notice that there is no degree sign used! Notice that there is no degree sign used! Kelvin scale is easier for scientists to use Kelvin scale is easier for scientists to use

Temperature Freezing Point Boiling Point Freezing Point Boiling Point Fahrenheit 32º F212ºF Celsius 0ºC100ºC Kelvin 273 K373 K Absolute Zero 0 K -273ºC

TEMPERATURE To convert Kelvin to Celsius – SUBTRACT 273 To convert Kelvin to Celsius – SUBTRACT 273 To convert Celsius to Kelvin – ADD 273 To convert Celsius to Kelvin – ADD 273

To calculate Kelvin you add 273 to the Celsius temperature To calculate Kelvin you add 273 to the Celsius temperature Ex. 23 ○ C = = 296 K Ex. 23 ○ C = = 296 K

Reading a Thermometer What’s the temperature? What’s the temperature? -14 ○ C 24.5 ○ C ○ C

Reading a Thermometer What’s the temperature? What’s the temperature? -14 ○ C 24.5 ○ C ○ C

Time Unit = second Unit = second Symbol = s Symbol = s Tool = stopwatch Tool = stopwatch

Time The period between 2 events The period between 2 events The SI unit of time is the second (s) The SI unit of time is the second (s) Measurement tool of time is a stopwatch Measurement tool of time is a stopwatch

Density Mass per unit of volume. Mass per unit of volume. Divide an objects mass by its volume. Divide an objects mass by its volume.

Derived Units Combination of SI units. Combination of SI units. Density = g/cm 3 Density = g/cm 3