Unit 1 Lecture Chapter 1

Science Science begins with being curious and allows us to discover new things. Observations are: 1. Qualitative- descriptive 2. Quantitative- numerical

Technology Applying scientific knowledge to help people is called technology. Technology changes, evolves, over time Ex: cell phones, TVs, computers

Branches of Science 1. Physical- Physics and Chemistry 2. Earth and Space- Geology and Astronomy 3. Life- Biology

Big Ideas of Physical Science 1. Space and time- the universe is old and big 2. Matter and change- matter has volume and mass, made of atoms which are made of protons, neutrons, and electrons 3. Forces and motion- force changes motion 4. Energy- kinetic and potential, can change form and be transferred

The Scientific Method Steps: 1. Observation 2. Form hypothesis 3. Test and collect data 4. Analyze data 5. Form conclusion in which you refer back to your hypothesis Scientists communicate findings in sci journals and at conferences

Hypothesis  Theory  Law Theory Well tested Becomes stronger the more evidence that is found to support it Explains how something happens Can be re-evaluated and changed based on new evidence Ex: Theory of Relativity, Theory of Evolution Law Explains patterns found in nature Can see these processes happening all around you all the time Ex: Law of gravity, Hubble’s Law, Gas Laws, Newton’s Laws

Scientific Models Help us understand things that are: Too big to see- the solar system Too small to see- the atom

Scientific Notation Used for very large or small numbers A product of a number between 1 and 10 and a power of ,000 = 3 x = 8.6 x ,000,000 = 0.322=

SI Units- an international system Base Units Lengthmeters m Massgramsg TempKelvinK Timesecondss Derived Units Area m 2 Volumem 3 Density g/mL or g/cm 3

Density Density = mass divided by volume Density = mass/volume D= m/v A block of aluminum occupies a volume of 15.0 mL and weighs 40.5 g. What is its density?

Conversions (train tracks) Centi:1m=100cm1g=100cg Milli:1m=1000mm1g=1000mg Kilo:1kg=1000g1km=1000m Convert 50.0 mL to liters How many millimeters are present in 20 km? How many seconds are in 2.0 years?

Measurements Sig figs- take it to 2 decimal places = = = = =

Temperature Conversions K = °C If you have Celsius, add 273 to get Kelvin If you have Kelvin, subtract 273 to get Celsius 0 Kelvin is called absolute zero Convert: 36°C = 259 K =

Organizing Data Data Tables X value vs. Y value Independent variable vs. dependent variable Graphs Line graphs compare something with time Bar Graphs just compare Pie Graphs compare percentages

Line Graphs The only type of graph we will use Slope Rise/Run Y value/ X value Direct proportion= both values increase Indirect proportion= one gets bigger, one gets smaller