Physics Topic 1 Measurements and Mathematics Physics Measurements

Physics Topic 1 Measurements and Mathematics

• Physics • Measurements and Mathematics • Obj: SWBAT perform unit conversions and assign the number of significant digits to a measurement • Do Now: What are some concerns you have for physics? • HW: Sign and return syllabus, sign up for Remind

• Physics • Measurements and Mathematics • Obj: SWBAT perform unit conversions and assign the number of significant digits to a measurement • Do Now: How many cm are in 3. 4 m? • HW: Sign and return syllabus, sign up for Remind

COPY THESE SI Units

SI Prefixes

Conversions • • • 1 Tera gram = 1, 000, 000 grams 1 Giga gram = 1, 000, 000 grams 1 Mega gram = 1, 000 grams 1 kilogram = 1, 000 grams 1 gram = 100 centi grams 1 gram = 1, 000 milli grams 1 gram = 1, 000 micro grams 1 gram = 1, 000, 000 nano grams 1 gram = 1, 000, 000 pico grams

Dimensional Analysis (a fancy name for changing units)

Tools for Measurement • Length • Force • Mass • Time • Angle

Making Measurements AND ONE MORE UNIT!!! • Read what the instrument says

Trigonometry

• • • Sin A Sin C Cos A Cos C Tan A Tan C • • • 20/29 21/29 20/21 21/20

• • • Sin A Sin C Cos A Cos C Tan A Tan C • • • 40/50 30/50 40/30 30/40

• • • Sin A Sin C Cos A Cos C Tan A Tan C • • • 36/39 15/39 36/15 15/36

• • • Sin A Sin C Cos A Cos C Tan A Tan C • • • 8/17 15/17 8/15 15/8

Uncertainty in Measurement • Precise – when data points are close to each other • Accuracy – when data points are close to the correct value

• Physics • Measurements and Mathematics • Obj: SWBAT perform unit conversions and assign the number of significant digits to a measurement • Do Now: How many Sig. Figs are in 3. 400 m? • HW: Sign and return syllabus, sign up for Remind

Significant Figures / Digits (Sig Figs) • Rules for counting 1. 2. 3. 4. All non-zero numbers count Zeros before a non-zero digit don’t count Zeros in-between non-zero digits count Zeros after non-zero digit only count if there’s a decimal point

How many significant figures are represented in each of the following numbers?

Adding and Subtracting • Answer has the fewest number of decimal places

Multiplication and Division • Answer has the fewest number of Significant Digits

Scientific Notation • Only count the coefficient for Significant Digits

Math with Scientific Notation • Add/Subtract power of 10 must be the same • Multiplication/Division

Rewrite the following numbers in scientific notation • • 4020 13796 0. 015 0. 0000007 1. 80 1 trillion 430, 000, 000

Graphs • Independent variable – what the experimenter changes (x-axis) • Dependent variable – what the experiment measures (y-axis)

Direct Proportions Direct Squared Inverse Constant Indirect Squared

Scalars and Vectors • Scalar – quantity with magnitude only • Vector – quantity with magnitude and direction