The Metric System Unit 0 Lesson 6

UNITS OF MEASUREMENT Scientists worldwide use a single system of measurement: System International d’Unites (International System of Measurements) or SI. Its main units of measurement are: Length: Meter (m) Volume: Liter (L) Mass: Kilogram (kg)

PREFIXES AND UNITS Prefixes indicate multiples or fractions of units of measurement. Units give specific meaning to numbers. Used together, prefixes and units provide information about ‘how much’ and ‘what’ was measured. It is common to refer to both the prefix and the unit as units or set of units. Prefix Meaning Kilo 1,000 Hecto 100 Deka 10 Deci 0.1 Centi 0.01 Milli 0.001

CONVERSION It is often necessary to convert one set of units to another. The conversion is done by finding the number of decimal places traversed or ‘jumped’ when moving from one prefix to another. Prefix Meaning Kilo 1,000 Hecto 100 Deka 10 Deci 0.1 Centi 0.01 Milli 0.001

CONVERSION EXAMPLE 1 Example: Convert 225 milliliters to hectoliters. How many ‘jumps’ is it from milli to hecto? Kilo – hecto – deka – (main unit) – deci – centi – milli There are 5 jumps to the left. Move the decimal point 5 places to the left, filling the empty spaces after the decimal point with zeroes. 225 milliliters = .00225 hectoliters Prefix Meaning Kilo 1,000 Hecto 100 Deka 10 Deci 0.1 Centi 0.01 Milli 0.001

CONVERSION EXAMPLE 2 Example: 15.78 kilograms = 1,578,000 centigrams To convert 15.78 kilograms to centigrams, move the decimal point 5 places to the right, filling in the extra space with zeroes. In this example the prefix is converted from what to what? And the unit is? Prefix Meaning Kilo 1,000 Hecto 100 Deka 10 Deci 0.1 Centi 0.01 Milli 0.001

GRAPHING Graphing is used to display data that is collected during a controlled experiment. A graph must contain 5 major parts: Title Independent variable (X axis) Dependent variable (Y axis) Scales for each variable Legend

PARTS OF A GRAPH The title should clearly depict what the graph is about. The independent variable is the variable which is controlled or predictable in an experiment. It is placed on the horizontal X axis. The dependent variable is what changes in response to the independent variable. It is placed on the vertical Y axis. Title

PARTS OF A GRAPH In order to know where to plot data points, scales must be used on both axes. Scales typically start at 0 and increase based on set intervals like 2, 5, 10, 20, etc. The scale will be dictated by your data. The legend is the description of the data. For example, if you are using a line graph and have multiple lines of different colors, the legend should explain what each color represents. Scales