Welcome to Class

Compare and contrast theories and laws

Agenda

• Quiz• Measurement notes– Measurement lab

Accuracy & Precision

• Accuracy:– Freedom form mistakes or errors;

Correctness

• Precision:– The ability to repeat; Repeatability

Units of Measurement• International System of Units (SI) • Makes sharing data and results easier

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Linear Measurement (straight lines)

• Length, Width, Height• Definition:

• Distance between two points• Tool:

•Meter stick, ruler• Base unit of measurement:

•Meters (m)

Area• Definition: – How much surface an object covers, 2-D

• Units of measurement: – m2, cm2 , etc.

• Formula: – A = L x W

Volume• Definition: – How much space an object takes up

• Two types of volume: – Regular and irregular

• Regular solids are box like– Volume is found by measuring length, width and

height• The volume of irregular objects is found by

water displacement

Volume (cont.)• Tool: – Regular = ruler or meter stick – Irregular = graduated cylinder

• Units of measurement:– m3, cm3 (for solids) – L , ml (for liquids)

• Formula: – V = L x W x H

• 1cm3 = 1ml

Welcome to Class

Define Accuracy and Precision

Agenda

• Finish Volume notes• Lab

Volume• Definition: – How much space an object takes up

• Two types of volume: – Regular and irregular

• Regular solids are box like– Volume is found by measuring length, width and

height• The volume of irregular objects is found by

water displacement

Volume (cont.)• Tool: – Regular = ruler or meter stick – Irregular = graduated cylinder

• Units of measurement:– m3, cm3 (for solids) – L , ml (for liquids)

• Formula: – V = L x W x H

• 1cm3 = 1ml

Volume Lab

Welcome to Class

How do you read a graduated cylinder?

Agenda

• Review measuring• Volume of regular objects lab

Volume• Definition: – How much space an object takes up

• Regular solids are box like– Volume is found by measuring length, width and

height

• Formula: – V = L x W x H

Volume of other Regular Objects

• Spheres – Formula : V = 4/3 πr3

• Cylinder– Formula: V = πr2 h

*π = 3.14Formulas are on Page 830 in the book

Measuring spheres/circles

• Measure end to end– Use paper on edge of spheres

• Measured diameter we need radius– Radius = ½ diameter– So: if d = 10 then r = 5

Volume of Regular Objects Lab

Welcome to Class

What is the formula we use for a sphere? Cylinder?

Agenda

• Finish measuring volume of regular objects• Mass notes• Mass Lab

Mass• Definition: – The amount of matter in an object

• Tool: – Triple beam Balance

• Base unit: – Grams (g) – A penny has the mass of about 1g

• 1g = 1cm3 for water only

Making a connection

• When you use water (and this works only for water)

1 ml = 1 cm3 = 1 g

Weight• Definition: – The gravitational pull on an object

• Tool: – Scale

• Base unit: – Newton (N)

Mass Vs. Weight

Temperature• Definition: – Measurement of the average kinetic energy of

molecules

• Tool: – Thermometer

• Base unit: – Celsius (co) and Kelvin (ko)

Mass Lab

Welcome to Class

List the common tools for measurement that we use to find linear measurements, volume and

mass.

Agenda

• Finish mass lab• Practice measuring

QUIZ TOMORROW!