3. What do you think about when You see the word PHYSICS? Physics is a branch of knowledge That involves the study of the Physical world.

4. Physics is Everywhere NameSubjectsExamples MechanicsMotionFalling objects ThermodynamicsHeat & TempMelting Vibrations & Waves Repetitive motions springs, waves OpticsLightMirrors, lenses ElectromagnetismElectricityCircuits RelativityMoving at high speeds Nuclear energy QuantumParticlesAtoms and parts

5. In Physics we will ONLY use The Metric System (or SI). Base QuantityBase UnitSymbol LengthMeterm MassKilogramkg TimeSeconds TemperatureKelvinK Electric Current AmpereA Luminous Intensity Candelacd

6. SI Prefixes PrefixSymbolScientific Notation TeraT10 12 GigaG10 9 MegaM10 6 Kilok10 3 Base1 Decid10 -1 Centic10 -2 Millim10 -3 Microµ10 -6 Nanon10 -9 Picop10 -12 Femtof10 -15

7. Significant Digits The digit in a measurement that is certain Plus the digit that is an estimate. For example, 31.7 has 3 significant digits When are digits significant and when are they not? Let’s read the rules and find out.

8. When a zero is not significant… A zero that is simply a place keeper Is not a significant digit, such as… 1040 This number has 3 sig. figs. 31.7 And this number has 2 3500

9. How do you know how many there are? The Atlantic-Pacific Rule!! Of course! If you can remember where the oceans are, you can remember this rule.

10. If a decimal point is present, count the significant digits from the Pacific side, that is, the left side. If a decimal point is absent, count from the Atlantic side, that is from the Right. Now, you should start counting from the 1 st non-zero digit that you find. All the Digits from to the end are significant, Including any zeros.

11. How many significant digits (sig. figs.) Are there in these numbers? 0.0026701 19.0550 3500 1809000 5 sig. figs. 6 sig. figs. 2 sig. figs. 4 sig. figs.

12. Your book, and you should too, Write many measurements with Decimals, this way whole numbers Stay meaningful. 100. 250.

13. Sig. Figs. In Calculations. When an exact number appears in A calculation, it does not affect the Number of sig. figs. In the final answer. In multiplication and division, the measurement With the smallest number of sig. figs. Determines the number of sig. figs. In the Answer.

14. In addition and subtraction, the number of Sig. figs. Allowed depends on the Number with the largest uncertainty. 3.05 X 2.10 X 0.75 = 4.80375 = 4.8 951.0 + 1407 + 23.911 + 158.18 = 2540

15. Practice these on your own… 12.7 km 3.0 35.6 L + 2.4 L 4.803 2.542 m X (16.408m – 3.88 m) = 4.2km = 7.91L = 31.85 m 2

16. Scientific notation is a short hand way Of writing really small or Really big numbers!! Such as … 227800000000 = 2.278 X 10 11 Or… 0.000000000000000000000000000000911 Is the same as 9.11 X 10 -31

17. Convert the following numbers to Scientific notation… a) 450000 b) 302000000 c) 0.00000045 a) 4.5 X 10 5 b) 3.02 X 10 8 c) 4.5 X 10 -7

18. Every year in science you get To hear about the scientific method. This is because anytime you do an Experiment, your results must Be reproducible! A Hypothesis is an educated guess. Typically the order is question, Hypothesis, experiment, measurements, Calculations, then summarize.

19. In the end you might come up With a new scientific law. A scientific law is a rule of nature That sums up related observations To describe a pattern in nature. You could also end up with a scientific Theory. A scientific theory is an explanation Based on many observations Supported by experimental results.

20. A measurement is a comparison Between an unknown quantity And a standard.

21. Your measurement is only as good As the thing you measure with! Precision describes the degree of exactness of a measurement. Accuracy describes how well the results Of a measurement agree with the actual value.

22. There are basically 2 different and Major ways to see data (measurements). Graphs and Tables We will use graphs almost all the time.

23. An independent variable is the Factor that is changed During the experiment The dependant variable is the factor That depends on the independent Variable.

24. Plotting a line graph… 1.Identify the independent variable and the dependant variable in your data. The independent variable is plotted on The horizontal axis and the dependant Variable is plotted on the vertical axis. 2. Determine the range of the variables To be plotted.

25. 3. Decide whether the origin is a valid point. 4. Spread the data out as much as possible. 5. Number and label the axis. 6. Plot the points on the graph. 7. Draw a best fit line. 8. Give the graph a title that Represents what is being shown.

26. Linear relationships have a straight line On a graph, and can be defined by The slope of that line. y = mx + b m = Δy / Δx Nonlinear relationships have Different shapes. (like a parabola)