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Chapter 1Chapter 1 A Physics Toolkit A Physics Toolkit

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1. Physics1. Physics

PhysicsPhysics -- study of the physical world: energy,study of the physical world: energy,matter, and how they are relatedmatter, and how they are related

Physics is a mathematical science. Just like youPhysics is a mathematical science. Just like you would use the English language to discuss a would use the English language to discuss anovel, you will be using math to discuss physicsnovel, you will be using math to discuss physics

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2. The SI System2. The SI System

F irst known as the Metric SystemF irst known as the Metric SystemDeveloped in F rance in the 1790s.Developed in F rance in the 1790s.

Is widely used in all but three countries.Is widely used in all but three countries.Has been adopted in the scientific community.Has been adopted in the scientific community.Missed being nationalized in the US in early Missed being nationalized in the US in early

1800s by one vote.1800s by one vote.

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2. The SI System Advantages2. The SI System Advantages

B ased on the decimal system. (powers of ten)B ased on the decimal system. (powers of ten)Uses PrefixesUses Prefixes

B ecause it is used almost world wide it makesB ecause it is used almost world wide it makescommercial trade easier.commercial trade easier.

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3. SI Fundamental Units3. SI Fundamental Units

Base QuantityBase Quantity NameName SymbolSymbolL engthL ength

MassMass Time Time

Temperature TemperatureElectric CurrentElectric Current

Amount of a Substance Amount of a SubstanceL uminous Intensity L uminous Intensity

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3. SI Fundamental Units3. SI Fundamental Units

Base QuantityBase Quantity NameName SymbolSymbolL engthL ength metermeter mm

MassMass kilogramkilogram kg kg Time Time secondsecond ss

Temperature Temperature KelvinKelvin KK

Electric CurrentElectric Current ampereampere ampamp Amount of a Substance Amount of a Substance molemole molmol

L uminous Intensity L uminous Intensity candelacandela cdcd

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4. Derived Units4. Derived Units

Combinations of 2 or more fundamental unitsCombinations of 2 or more fundamental unitsExamples:Examples:

SpeedSpeed m/s or km/hrm/s or km/hr Volume Volume -- mm33 or liters ( L )or liters ( L )

1 L iter = 1000 cubic centimeters1 L iter = 1000 cubic centimeters

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5. Common Prefixes5. Common PrefixesPrefixPrefix SymbolSymbol ConversionConversion

MegaMega-- MM 1Mm= 1,000,000 m1Mm= 1,000,000 m

kilokilo-- k k 1 km = 1000 m1 km = 1000 m

decideci-- dd 10 dm = 1 m10 dm = 1 m

centicenti-- cc 100 cm = 1 m100 cm = 1 m

millimilli-- mm 1000 mm = 1 m1000 mm = 1 m

micromicro-- 1,000,0001,000,000 m = 1 mm = 1 m

nanonano-- nn 1,000,000,000 nm = 1m1,000,000,000 nm = 1m

Note: any unit can be used instead of meters

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6. Dimensional Analysis6. Dimensional Analysis1.1. 45 cm to m45 cm to m2.2. 98.2 kg to g 98.2 kg to g 3.3. 874 mm to km ( 874 mm to km ( must convert to base units must convert to base units

11 st st ) )4.4. 7784.1 cg to mg 7784.1 cg to mg

5.5. .00956 kg to.00956 kg to g g 6.6. 3.4 m3.4 m22 to cmto cm22 (**M ust use math rules for(**M ust use math rules for

powers) powers)

7.7. 875 cm875 cm33

to dmto dm33

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7 . Scientific Notation7 . Scientific Notation

Scientific Notation makes it easier to expressScientific Notation makes it easier to express very large and small numbers very large and small numbers

1.1. The first number will always be between 1 and The first number will always be between 1 and10.10.2.2. The last part will always be 10 raised to some The last part will always be 10 raised to some

power.power.3.3. ****Make sure that you can enter scientific****Make sure that you can enter scientific

notation into your calculator!!!!!notation into your calculator!!!!!

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7 . How to do it7 . How to do it

L ocate the decimal point and move it so there isL ocate the decimal point and move it so there isone leading digit.one leading digit.

29,190,000,000 becomes 2.91929,190,000,000 becomes 2.919Now count how many places you moved theNow count how many places you moved thedecimal point and place it in the exponentdecimal point and place it in the exponentposition. (If you moved left the exponent isposition. (If you moved left the exponent ispositive.positive.

2.919 x 102.919 x 101010

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7 . Looks goodBut Not Really7 . Looks goodBut Not Really

Is this number in correct scientific notation?Is this number in correct scientific notation?428.5 x 10428.5 x 1099Nope.Nope.

You fix it the same as before. You fix it the same as before.Move the decimalMove the decimal

4.2854.285

Then fix the exponent. Since you moved the decimal Then fix the exponent. Since you moved the decimalto the left 2 raise the power 2.to the left 2 raise the power 2.4.285 x 104.285 x 101111

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7 . Practice M akes Perfect7 . Practice M akes Perfect

1.1. 28,000,00028,000,0002.2. 305,000305,000

3.3. 0.000004630.000004634.4. 0.00340.00345.5. 2101 x 102101 x 1055

6.6. 0.0029 x 100.0029 x 10--3232

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7 . Some Practice7 . Some Practice

1.1. 7.3 x 107.3 x 1022 + 4.5 x 10+ 4.5 x 1022 ==2.2. 5.9 x 105.9 x 1099 -- 3.2 x 103.2 x 1088 ==3.3. 2.30 x 102.30 x 1044 -- 4.50 x 104.50 x 1022 ==4.4. (1.5 x 10(1.5 x 10--22 )x(3.0 x 10 )x(3.0 x 10--22 ) = ) =5.5. (4.5 x 10(4.5 x 1055 )/(1.5 x 10 )/(1.5 x 10 22 ) = ) =6.6. (9.0 x 10(9.0 x 1088 )/(3.0 x 10 )/(3.0 x 10 --33 ) = ) =

1.1. 1.18 x 101.18 x 1033

2.2. 5.6 x 105.6 x 1099 (rounded)(rounded)3.3. 2.26 x 102.26 x 1044

4.4. 4.5 x 104.5 x 10--44

5.5. 3.0 x 103.0 x 1033

6.6. 2.7 x 102.7 x 101111