physical science ch2: sec1

Physical Science:Physical Science:CH 2 , Sec 1CH 2 , Sec 1Page 40Page 40

Warm Up Warm Up

Make a list of Make a list of

observations observations

about the pictureabout the picture Form a scientific question about the picture.Form a scientific question about the picture. Make a hypothesis. Make a hypothesis. Describe data and tools you would need to test Describe data and tools you would need to test

your hypothesis.your hypothesis.

Data in Science Data in Science

The Big Idea: The Big Idea: Scientists use tools to collect, organize, and Scientists use tools to collect, organize, and

analyze data while conducting analyze data while conducting investigations. investigations.

Tools must be accurate. Tools must be accurate.

International System of International System of UnitsUnits

(AKA Metric System)(AKA Metric System) Universal system for scienceUniversal system for science System works by multiples of 10System works by multiples of 10

Metric System Metric System Conversions Conversions

Brain Pop KKing ing HHenry enry DDoesn’t oesn’t UUsually sually DDrink rink CChocolate hocolate MMilk ilk KKilo, ilo, HHecto, ecto, DDeckeckaa, , U Unit, nit, DDeci, eci, CCenti, enti, MMiliili

Put your pencil on the unit you are starting withPut your pencil on the unit you are starting with Loop from letter to letter until you reach the unit you want. Loop from letter to letter until you reach the unit you want. Count the loops Count the loops Move the decimal that many times in the same direction you Move the decimal that many times in the same direction you

move the pencil move the pencil

Units Units

LengthLength is in is in meters (m)meters (m) MassMass is in is in grams (g)grams (g) VolumeVolume is in is in liters (L) or metersliters (L) or meters3 3 (m(m33))

1mL = 1cm1mL = 1cm33

DensityDensity is measured by is measured by Mass / VolumeMass / Volume grams/ liters or metersgrams/ liters or meters3 3 ( 1 g/cm( 1 g/cm3 or 3 or 1 g/L)1 g/L)

Temperature Temperature

TemperatureTemperature is in is in Kelvin (K)Kelvin (K) or degrees or degrees Celsius (°C)Celsius (°C), (Not Fahrenheit) , (Not Fahrenheit)

0°Celsius = 273 Kelvin 0°Celsius = 273 Kelvin To convert Celsius to Kelvin just add 273 To convert Celsius to Kelvin just add 273

100°C + 273 = 373 K 100°C + 273 = 373 K

Practice Practice

What is the density of an object with a What is the density of an object with a mass of 15g and volume of 3 cmmass of 15g and volume of 3 cm33??

Normal body temperature is 37°C, what Normal body temperature is 37°C, what is that in Kelvin?is that in Kelvin?

26 cm = ____ hm 26 cm = ____ hm 91 m = ____ km 91 m = ____ km 6 km = ____ mm 6 km = ____ mm

Practice AnswersPractice Answers

15g ÷ 3cm15g ÷ 3cm33 = 5 g/cm = 5 g/cm33

37°C + 273 = 310 K37°C + 273 = 310 K 26 cm = 0.0026 hm 26 cm = 0.0026 hm 91 m = 0.091 km 91 m = 0.091 km 6 km = 6,000,000 mm6 km = 6,000,000 mm

HomeworkHomework

TO BE COMPLETED IN NOTEBOOKTO BE COMPLETED IN NOTEBOOK Define Vocabulary words on page 42: Define Vocabulary words on page 42:

Mass, volume, density, temperature, model, Mass, volume, density, temperature, model, theory, and law.theory, and law.

Section Review page 49: Section Review page 49: Questions: 1, 3, 4, 5, 12Questions: 1, 3, 4, 5, 12

Models in Science

Models are representations of an object or system.

Physical Models

Show an example at a reasonable scale. Examples: model airplanes, model solar

system, model of an atom.

Conceptual Model

Explains or summarizes with words Big Bang Model:

12 to 15 billion years ago an event called the big bang sent matter in all directions. This matter eventually formed the galaxies and planets.

Mathematical Models

Uses math to represent the physical world. Simple math models:

Force = Mass x Acceleration E=Mc2

Complex math models: Quantum Mechanics wave function of a particle:

Limits of Models

A model is not exactly the same as the real thing it represents Example: There are many limitations of this

model of the solar system: Can you find some?

Scientific Theories

Theory is an explanation for many hypotheses and observations.  theory of evolution, the theory of relativity, the atomic theory, and the quantum theory

Theories can be changed.

Scientific Laws

A summary of many experimental results and observations.

Only tells you what happens, (not why or how) The law of gravity, Newton's laws of motion, Conservation of mass

Homework 9/21/10

TO BE COMPLETED IN NOTEBOOKTO BE COMPLETED IN NOTEBOOK Due 9/22/10 Due 9/22/10 Section Review page 49: Section Review page 49:

#s 2, 6 -11, and 13 #s 2, 6 -11, and 13