1. Intro to Physics Pg. 3 in NB

2. Intro Topics: Scientific notation Units Conversions/dimensional analysis Rearranging formulas/equations

3. Scientific notation is a system that makes it easy to work with the huge range of numbers needed to describe the physical world. Even very large or very small numbers can be simply expressed as a coefficient multiplied by a power of ten. Example: 4,300 can be changed to 4.3 x 10 3 Scientific notation

4. Powers of ten are 10, 10 2 = 100, 10 3 = 1000, 10 4 = 10,000 and so on. Exponent is the # of times you had to shift the decimal to get your coefficient. The coefficient is a decimal number between 1 and 10. To get coefficient shift decimal until it’s behind the first NON-ZERO #.

5. For numbers GREATER than one, scientific notation uses POSITIVE exponents: Example: 1500 turns into 1.5 x 10 3 Numbers greater than one

6. For numbers LESS than one, scientific notation uses NEGATIVE exponents: Example:.0015 turns into 1.5 x 10 -3 Numbers less than one

7. Powers of ten

8. Calculators and computers use the symbol E or EE for powers of ten. NO MORE CARROT! The letter E stands for “x 10” so whatever you put AFTER the E represents the exponent. Powers of ten on a calculator

9. Engaging with the concepts Write how these numbers would look in scientific notation on paper & in the calculator: a.) 4,180 joules  On paper: 4.18 x 10 3 joules  Calculator: 4.18 E3 b.).035 meters  On paper: 3.5 x 10 -2 meters  Calculator: 3.5 E -2

10. Assessment a.275 2.75 x 10 2 b.0.00173 1.73 x 10 -3 c. 93,422 9.3422 x 10 4 d. 0.000018 1.8 x 10 -5 Correctly write the following in scientific notation (how you would write it on paper, NOT in the calculator):

11. Units are a key to telling you what quantity you’re dealing with. Memorizing units will greatly help you succeed this year! EVERY answer MUST have UNITS with it! Units are like clothes for your #’s, we do NOT want any naked #’s! Example  You calculate that a ball traveled a distance of 5 meters. WRONG way to record answer  5 RIGHT way to record answer  5m or 5 meters Importance of Units

12. In the SI system, mass has units of grams (g) and kilograms (kg). One kilogram = 1000 grams. Measuring mass

13. There are two common systems of length units you should know: The English system uses inches (in), feet (ft) and yards (yd). The metric system using millimeters (mm), centimeters (cm), meters (m), and kilometers (km). Length The meter is the SI base unit for length.

14. Time Time is a fundamental quantity. The SI unit of time is the second.

15. Graphing You will have to be able to construct line graphs this year to illustrate motion of an object Things you must be able to do: –Title the graph –Label the x & y axis –Scale the values for the x & y axis –Plot data points –Take the slope of a line

16. Graph Basics Label the x & y axis Label whether x & y are positive or negative in each quadrant Independent vs. dependent variable – X axis  – Y axis 

17. Find the slope of the following Each scale is increasing by 1

18. Plotting & slope Plot the following data & find the slope of the line

19. Conversions Sometimes you’ll have to convert a value given to you before you can complete a problem. Example: You’re asked for a distance in meters but you’re given a distance in feet.

20. What you’ll need to be able to do: There are 3 ways you could have to convert this year: –English to metric or metric to English –Change between metric units –Change between time units

21. Converting between Metrics If converting between metric units you just shift the decimal! The “B” for base represents the spot for: m (meters), g (grams), s (seconds)

22. Example

23. When solving physics problems, the units you use must be consistent. You need to be able to convert units to make them consistent. To convert a quantity from one unit to another, multiply by a conversion factor. A conversion factor always has the value of one (1) whether it is right-side-up or upside-down. Converting units

24. Converting Units When you’re converting units, you “cancel” out units diagonally

25. To convert from one unit to another, multiply by the appropriate conversion factor. Converting other units Pick the conversion factor that lets you cancel the unit you don’t want, and end up with the unit you want. Always “cancel” diagonally

26. Test your knowledge Convert 12 inches to centimeters. What conversion factor should we use to go from inches to centimeters? Answer: 30.5 cm

27. Converting Unit Fractions Converting units in fractions is a little different Ex 1: Convert 10m/s to cm/s. Ex 2: Convert 10m/s to m/hr.

28. Example 1 Convert 10m/s to cm/s. Ans: 1,000 cm/s

29. Example 2 Convert 10m/s to m/hr. Answer: 36,000 m/hr

30. Double conversions Double the Fun! Convert 10m/s to mi/hr (i.e. mph) Answer: 22.4 mi/hr

31. Assessment 1.Which of the following unit conversions is correct? A. B. C.

32. Suppose this is the formula: But the variable you are asked for is time d. What do you do? Solving for a variable