Ch. 1.2 Measuring with Scientific Units

OBJECTIVES Identify the base units used in the SI system Explain the use of Scientific Notation Compare Volume, Mass, and Density Measure Length, Mass, and Temperature using SI units

Standards Addressed S6a-Use tools to observe and measure objects with appropriate precision & accuracy S4a-Big ideas and unifying concepts, such as order and organization

Systèmé International (SI) Base 10 system!! See Table 1.2, page 11 –Length: meter –Mass: kilogram –Time: second

Volume The amount of space that something occupies SI unit is the cubic meter (m 3 ) Smaller volumes measured with the cubic centimeter (cm 3 ) 1 cm 3 = 1 milliliter (ml) Graduated cylinder measures liquid volume Measure at the bottom of the meniscus of the meniscus

Mass & Weight Weight depends on gravity Mass does NOT!! Mass is the amount of matter (or STUFF) in an object SI unit of mass is the kilogram

Density The amount of matter packed into a given volume Mass / volume Units are grams / cm 3 Density is a characteristic property of a substance Density of water is 1g / cm 3 Why will these objects sink or float in water?

Temperature Measure of heat energy Measured with a thermometer SI temperature scale is Celsius Water freezes at 0° C (32° Fahrenheit) Water boils at 100° C (212° Fahrenheit)

Time SI unit is the second 1 millisecond = ? 1/1000 of a second 60 sec = 1 minute 60 minutes = 1 hour 24 hours = 1 day 365 days = 1 year How many seconds in an hour? How many hours in a year?

Scientific Notation Is there an easier way to write 23,000,000,000,000,000,000? YES!!!! Step 1: Make the number between 1 and 10 by placing the decimal to the proper “ new position” Step 2: Write the “new” number, followed by “ x 10 n ” Step 3: Count the number of places the decimal point moved from its original position to its new position Step 4: Put the number of places moved in place of the “n” (This is called an exponent)