Measurement and Dimensional Analysis Unit 1

Making Measurements Length - the distance between any two points (m or cm) Mass - the quantity of matter in an object (kg or g) Volume - a measure of space, in cubic units (m3 or cm3) Weight - the force with which gravity pulls on a quantity of matter (measured in Newtons) Temperature - the degree of hotness or coldness of a body or environment (measured in Celsius or Kelvin)

Units of Measurement Scientists use the International System of Units (SI) for consistency Quantity Unit Abbreviation Length meter m Mass kilogram kg Time second s Temperature kelvin K Electric Current ampere A Amount of substance mole mol

SI Prefixes for large measurements 1 km = 1,000 m Prefix Symbol Meaning Multiple of base unit kilo- k thousand 1,000 mega- M million 1,000,000 giga- G billion 1,000,000,000

SI Prefixes for small measurements Symbol Meaning Multiple of base unit deci- d tenth 0.1 centi- c hundredth 0.01 milli- m thousandth 0.001 micro- μ millionth 0.000 001 nano- n billionth 0.000 000 001 1 centimeter = 0.01 meters

Calculating Volume of a Box Measure the length. Measure the width. Measure the height. Calculate the volume V = l * w * h Units3 (cm3, m3, etc)

Calculating Volume of a Box Practice Calculation! What is the volume of this box? V = l * w * h

Reading a Graduated Cylinder Always look at the graduated cylinder at eye-level (not above it or below). Always measure the volume from the BOTTOM of the menicus (the curved surface of the liquid)

Warm Up Open up to page 12 in your notebook, and answer the following question IN COMPLETE SENTENCES: How can this information be used in everyday life? What types of measurements will I be using in my future jobs?

Key Conversion Factors 1 cm = 10 mm 1 m = 100 cm 1 m = 1000 mm 1 km = 1000 m *The base unit (meters) can be changed to other units (grams, liters, etc). Prefixes remain the same (centi-, milli-, kilo-)

Dimensional Analysis So, how do we know how many meters are in 4.6 kilometers? We use dimensional analysis to convert from one unit to another!

Dimensional Analysis Write down what you know, with units. Set up a T-chart. Fill in the units FIRST, making sure that given units cancel out. Add your key conversion factor into your T- chart. If necessary, continue steps 3 and 4 until you reach your desired answer.

Practice # 1 So, how do we know how many meters are in 4.6 kilometers? Write down what you know, with units. Set up a T-chart. Fill in the units FIRST, making sure that given units cancel out. Add your key conversion factor into your T- chart.

Practice Convert 13 cm to m. Convert 1.7 m to mm. Convert 16 cm to mm. Convert 1987 km to m. Convert 98 m to cm. Convert 13890 mm to m. Convert 189 mm to cm.