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GRADE ELEVEN PHYSICS SPH 3U(G) MR. MOORS Rodney.Moors@ocdsb.ca PICK UP A TEXTBOOK and CD TEXTBOOK - $80 CD - $10 Student email.
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GRADE ELEVEN PHYSICS SPH 3U(G) MR. MOORS Rodney.Moors@ocdsb.ca PICK UP A TEXTBOOK and CD TEXTBOOK - $80CD - $10 Student email
Physics is the original science that studies the physical world.It used to be known as natural philosophy.Today it is mostly concerned with the behaviour and structure of matter. The study of physics often leads to mathematical relationships. These relationships are useful because they describe the nature of matter and they allow the accurate prediction of future events. PHYSICS IS MATHEMATICAL. PHYSICS CAN BE ABSTRACT, YOU MUST THINK. PHYSICS DEMANDS HARD WORK.
SAY THE F-WORD OR ABOVE?????? • (I decide what is above or below, e.g. the s-word is below) • THREE CHOICES • DO TEN PUSH-UPS • DO TWENTY CRUNCHES • SING I’M A LITTLE TEAPOT (with proper actions) IN FRONT OF CLASS • (this could also be foisted upon you in the halls!!)
KEEP THIS ROOM CLEAN AND NEAT!!!! -put away equipment -throw out garbage and recyclables properly -all are expected to pitch in -if we cannot do this restrictions will follow All due dates, notes, assignments, labs, etc. can be found at moorsscience.wikispaces.com
Using a Calculator Do the following calculations by pressing your calculator as few times as possible. The physics in this course is challenging but 90% of the difficulties arising in solving physics problems come from small math mistakes (what I call little math). When difficulties arise the first thing to do is look over every step of your calculation or have someone else look it over.
SIGNIFICANT DIGITS Two types of quantities are used in science: exact values and measurements. Exact values include defined quantities (1 kg is 1000 g) and counted values ( 12 donuts). Measurements are not exact because they always include some degree of uncertainty. A measurement is made up of numbers that are certain and one digit, the last one that is estimated or uncertain. Digits that are part of the measurement are significant while digits that are not part of the measurement are insignificant.A few rules will help distinguish this statement. -all non-zero digits and in-between zeroes are significant -zeroes in front of all of the non-zero digits are insignificant -zeroes behind all of the non-zero digits and behind the decimal point are significant
-zeroes behind all of the non-zero digits but before the decimal may be significant orinsignificant (assume significant unless you know where the estimated value of the measurement actually is) -use scientific notation to show how many significant digits are present 40025 360.20 0.00450 2600 2600.0 850000 12401 0.00007 4.0025 x 104 3.6020 x 102 4.50 x 10-3 2.6 x 103 2.6000 x 103 8.5 x 105 1.2401 x 104 7 x 10-5 5 5 3 2-4 5 2-6 5 1
Calculations and Significant Figures Performing the actual calculation and tracking significant figures is the only real way to ascertain the number of significant figures that make up the correct answer. Whenever an estimated value is part of a calculation the number it produces is estimated. Simplified rules have been developed to make these calculations easier.
Adding and Subtracting When adding and subtracting, the answer should be precise to the same number column as the most imprecise number in the calculation. Multiplying and Dividing When multiplying and dividing, the answer should have the same number of significant digits as the number in the calculation which has the fewest significant digits.
The rules and procedures you have seen apply to measured values.They will be utilized in lab write-ups or in other lab based evaluations where indicated. On tests, quizzes or assignments you have a choice. You can perform calculations following the rules above or you can simply always use four significant figures and only 4 significant figures. You must let me know at the beginning of assignment if you are using the four significant figure method. homework: complete significant figures worksheet
UNIT CONVERSION The metric system will be used in this unit so conversions with prefixes will be performed. The units of time also often need to be converted.
Convert the following measurements to the units stated. -express answer in scientific notation -express answer to 4 significant digits (round properly) a) 6.42 km to m b) 1478 s to hr c) 52.3 km/hr to m/s d) 34.5 Mm to mm e) 45.9 nm to km f) 79 m/s to km/hr g) 45.6 km/hr2 to m/s2 h) 0.239 m/s2 to km/hr2 go over unit scale and conversion
Answers • 6.420 x 103 m b) 4.106 x 10-1 hr • c) 1.453 x 101 m/s d) 3.450 x 1013mm • e) 4.59 x 10-11 km f) 2.844 x 102 km/hr • g) 3.519 x 10-3 m/s2 h) 3.097 x 103 km/hr2
REARRANGING EQUATIONS Rearrange the following equations so that the letter indicated is isolated on the left hand side of the equals symbol.
a) g) n W b) W h) t r c) Dd d) x i) e) R j) f) r2 v2