Metric System Measurement

The English system uses measurements like feet, yards, miles, and gallons. Also known as the International System of Units or the SI system

SI Units International System of Units Base Units Length Mass Volume Temperature Time meter (m) gram (g) liter (L) Celsius (C) seconds (s)

The metric system is a system of measurement based on the number 10 Common SI prefixes: Kilo- (k) means 1,000 Hecto- (h) means 100 Deka- (da) means 10 Deci- (d) means 0.1 (one tenth) Centi- (c) means 0.01 (one hundredth) Milli- (m) means 0.001 (one thousandth)

Conversions between large and small quantities K H D B d c m King Henry Died By drinking chocolate milk This chart tells you three things: How many places to move the decimal In what direction to move the decimal What base unit to use

K H D B d c m Examples: 4.51 kg = ________g 4587m = _________mm 1.23 mL = ________L

Answers… Kg Hg Dg g dg cg mg 4 5 1 4.51 kg = 4510 g

m dm cm mm 4587 4587m = 4,587,000mm

l dl cl ml 0 0 0 1 23 mL 1.23 mL = 0.00123 L

Length measure distance The basic unit or SI unit of length in the SI system is the meter (m). To measure objects smaller than a meter scientists use the centimeter (cm) or the millimeter (mm) 100 cm = 1 meter 1000 mm = 1 meter For larger measurements, scientists use kilometers. 1000 m = 1 km Measured with a metric ruler or meter stick

Mass measures amount of matter The basic unit or SI unit of mass in the SI system is the gram (g). To measure the mass of large objects you will use a unit known as a kilogram It is useful in measuring the mass of bicycles, cars, or people. To measure the mass of smaller objects you will use a unit known as the gram (g) Measured with a balance or digital scale It is useful in measuring the mass of a paper clip, thumb tack, staple. There are 1,000 grams in a kilogram.

Measuring Mass Digital Scale Triple-beam balance

The Difference Between Mass and Weight Weight is a measure of the force of gravity acting on an object. Measure weight by using a scale. When you stand on a scale gravity pulls you downward. However, if you weighed yourself on the moon you would weigh less. Mass is a measure of how much matter an object contains, it remains constant no matter where an object may be. Your mass is the same on the moon as it is on Earth. ** The weight of an object may differ on the moon, or on earth, but the mass stays the same**

Measuring Volume of Liquids Volume is the amount of space an object takes up. To measure the volume of a liquid, you will use a base unit or SI unit known as a liter (L). You can measure large liquid volumes in kiloliters (kL) You can measure smaller liquid volumes in milliliters (mL) 1,000 mL = 1 L Measured with a graduated cylinder

Graduated Cylinder Scientists commonly use a graduated cylinder to measure liquid volumes. The graduated cylinder is marked off in milliliter segments. When liquid is poured into a graduated cylinder, the top surface of the water is curved. This curve is called the meniscus. To determine the volume of the water, you should read the bottom of the meniscus

Volume of Rectangular Solids The basic unit or SI unit to measure the volume of a solid object is a cubic centimeter (cm³) A cubic centimeter is equal to the volume of a cube that measures one centimeter on each side. 1 cm³ = 1 mL For solids with larger volumes, scientists use the SI unit known as the cubic meter (m³). A cubic meter measures one meter on each side. Measured with a formula: Volume = length x width x height

Volume of Irregular Solids If you wanted to find the volume of an object that you could not determine the length, width, and height (example: rock), you would immerse the object in water and see how much the water level rises. You would subtract the amount of water that you started with from the amount of water that the object forced the water to rise to and you would know the volume of your object. Known as water displacement

Density Density is a measure of how much mass is contained in a given volume. To calculate density you divide the mass by the volume: Density = Mass Volume

Density Because density is actually made up of two other measurements – mass and volume - an object’s density is expressed in two units. Two common units of density are grams per cubic centimeter (g/cm³) for regular solid items and grams per milliliter (g/mL) for irregular solid objects. The numerator is the measure of mass while the denominator is the measure of volume

Densities of Common Substances Substance Density (g/cm³) Air 0.001 Ice 0.9 Water 1.0 Aluminum 2.7 Gold 19.3 The density of an object stays the same no matter how large or small a sample of the substance is.

Density An object will float if it is less dense than the surrounding liquid. A piece of wood with the density of 0.8g/cm³ will float in water because the density of water is 1.0 g/cm³ A ring made of pure silver with a density of 10.5 g/cm³ will sink in water because it is more dense.

Time Time is the period between two events The basic unit or SI unit of time in the SI system is the second (s). Clocks and stopwatches are used to measure time Common Conversions for Time 1s = 1,000 ms (milliseconds) 1 min = 60 s 1 h = 60 min

Temperature The measurement of how hot or cold something is (measurement of heat) The basic unit or SI unit of temperature in the SI system is the Celsius scale (°C). Water freezes at 0°C or 32°F Water boils at 100°C or 212°F Normal human body temperature is 37°C or 98.6°F Temperature is measured with a thermometer. Place the thermometer in a substance and wait for the liquid in the thermometer to stop moving. Then read the number next to the top of the liquid in the thermometer.

Temperature Scales