fowler chapter 1 lecture 2 basic concepts. scientific notation (powers of ten) see table 2-1, p33...
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SCIENTIFIC NOTATION (powers of ten)SEE TABLE 2-1, P33
ANY NUMBER CAN BE EXPRESSED AS BASE x10 EXPONENT
(CAN BE POSITIVE OR NEGATIVE) + OR -
OTHER BASES AND EXPONENTS 32 53 8125
ANY NUMBER RAISED TO THE ZEROTH POWER IS EQUAL TO ZERO
EXAMPLES: 10 1100 11000,11,12 000
WRITE 1000 IN SCIENTIFIC NOTATION
33 100.1101000 1000 WRITE AS 1 FOLLOWED BY 3 ZERO’SANY NUMBER >0 CAN BE EXPRESSED THIS WAY.
EXAMPLE: 1,237 CAN BE EXPRESSED AS 1.237X10³
COUNT THE NUMBER OF DECIMAL PLACES TO THE RIGHT OF THE FIRST DIGITTHEN PLACE THE DECIMAL PT. AFTER THE FIRST DIGIT. 1.237
1.237 THE NUMBER OF DECIMAL PLACES TO THE RIGHT OF THE FIRST DIGIT IS THE EXPONENT EXPRESSED AS THE POWER OF TEN, IN THIS CASE IT IS 3
1,237 =1.237X10³
FOR NEGATIVE EXPONENTS(ANY NUMBER <0) FOLLOW THE PROCEDURE ON THE PRIOR SLIDE, BUT IN THE REVERSE DIRECTION.
EXAMPLES: 10 0.1 =¹־ 10 0.01 =²־ 10 0.001 =³־HERE WE COUNT DECEMICAL PLACES TO THE LEFT INSTEAD OF THE RIGHT.
EXAMPLE: 10 0.001 =³־
0.001= 10 ³־ COUNT 3 PLACE TO THE LEFT.
FROM OUR LAST EXAMPLE LET’S WRITE 0.001237 IN S. N.COUNT FROM THE FIRST DIGIT TO THE LEFT.
.001237 -3 IS THE EXPONENT FOR THIS POWER OF TEN.
SO .001237= 1.237X10 ³־
1,237 CAN ASLO BE EXPRESSED AS
12.37X10²=1,237
OR 123.7X10¹=1,237
DEPENDING ON WERE THE DECIMAL PT. IS PLACED, BOTH RESULTS GIVE THE NUMBER.
.001237 CAN ASLO BE EXPRESSED AS
1.237X10 001237= .³ ־
OR 0.1237X10 001237= .²־
DEPENDING ON WHERE THE DECIMAL PT. IS PLACED, BOTH RESULTS GIVE THE NUMBER.
ENGINEERING NOTATION
IN THIS SYSTEM POWERS OF TEN ARE ALWAYS MULTIPIES OF 3
963 10,10,10 …ETC.
963 10,10,10 OR
EXAMPLE: EXPRESS 27000 IN S.N. AND E.N. S.N. 4107.2
E.N. 31027
ELECTRICAL UNITS AND SYMBOLS TABLE 2-3 P.37
QUANTITY UNIT SYMBOL
CURRENT AMPERE(A) I
VOLTAGE VOLT(V) V
RESISTANCE OHM(Ω) R
FREQUENCY HERTZ(Hz) f
CAPACITANCE FARAD(F) C
INDUCTANCE HENERY(H) L
POWER WATTS(W) P
EXAMPLES : USES OF ENGINEERING NOTATION (E.N.)
1,000,000Ω = 6101 = 1MΩ
27,340Ω = 410734.2 =27.34X10³Ω =27.43KΩ IN E.N.OR .0274MΩOR O.OOO274GΩ
0.000546Ω =.546X10 ³־ Ω = .546mΩ =546uΩ =546000nΩ
QUICK MATH REVIEW
4 OPERATES IN ALL OF MATHEMATICS
ADDITIONSUBTRACTIONMULTIPICATIONDIVISION
DIVISION AND MULTIPICATION CAN BE DERIVATED FROM ADDITION AND SUBTRACTION.
MULTIPICATION IS A SERIES OF REPEATED ADDITIONS
EXAMPLE: 2X4=8 OR 2+2+2+2=8
DIVISION IS A SERIES OF REPEATED SUBTRACTIONS
EXAMPLE:
224
426
628
248
SIMPLE ALGEBRA
ANY QUANTITY ON BOTH SIDES OF AN EQUATION ARE EQUAL.
EXAMPLES V=V EXAMPLES I=I R=R
ADDITION V+V=2V 1+1=2SUBTRACTION V-V=0 1-1=0
2V-V=V
A+B=C
ANY QUANTITY CAN BE ADDED OR SUBTRACTED TO BOTH SIDES OF ANY EQUATION.
GIVEN A+B=C
SOLVE FOR ASINCE -B=- B, ADD THIS TO BOTH SIDES OF THE EQUATION.
A+B-B=C-B
SINCE B-B=0
A+0=C-B A=C-B
SOLVE FOR B A+B=C ADD –A TO BOTH SIDES. A+B-A=C-A B+A-A=C-A B+0=C-A B=C-A
LAWS OF EXPONENTS
V CAN ALSO BE EXPRESSED AS V¹, SO V=V¹
ANY QUANTITY DIVIDED BY ITSELF= 1
SINCE 1/V=1/V V=V V(1/V) =V(1/V) V(1/V) =V(1/V)
1=1
1/V CAN BE WRITTEN AS V ¹־
1/V=V ¹־
OR XVVX /1
V/V = 1 OR V¹/V¹ =V¹ ¹־ =Vº =1
EXAMPLE: V²/V =V²/V¹ = V² ¹־ =V¹ =V
OR VxV/V = VxV/V =V
YXYX VVV /
EXAMPLE: VVVVV /1/ 13232
XXX RVRV //
EXAMPLE: 222 // RVRV
OR 22 /// RVRVRV
SQUARE ROOTS
WE CAN RAISE A BASE NUMBER TO ANY POWER
8² =64
LETS REVERSE THIS PROCESS
FIND 64
IS DEFINED AS A RADIAL SIGN
2 ANOTHER WAY OF SHOWING THE SAME THING
X2 64INDEX
INDEX: HOW MANY TIMES WAS THIS NUMBER X MULTILED BY ITSELF TO GET 64
864
64882
ANOTHER WAY TO EXPRESS THIS
222222228
8888886464
13/33/133 333
12/22/122/12/12 1
283
Y XYX VV /
VVVVV
VVOR
VV
12/22/122 2
2/12
2/1
)(EXAMPLE:
ASDEFINEDISMEANSSYMBOL
OHM’S LAW
IRV
RIV
RIV
RIV
IV
R IS A PROPORTIONIALITY CONSTANT
THE PRODUCT IR CAN BE WRITTEN SEVERAL WAYS IRRIRI
.INCREASINGISQUANTITYAMEANS
.DECREASINGISQUANTITYAMEANS
V=IR SOLVE FOR IMULTIPLIE BOTH SIDES BY 1/R
(1/R)V=IR(1/R)
V/R=IR/R
V/R=I R/R
V/R=I(1)
V/R=I
OR I=V/R
HOW CAN WE INCREASE I
RVI
VI
RTVI
RVI
/
/
/
ONE WAY IS TO INCREASE V
OR DECREASE R
I IS INVERSELY PROPORTIONAL
TO R. AS R ↓, I↑
IF WE WANT TO DECREASE I, ↑R
RVI /
I IS INVERSELY PROPORTIONAL
TO 1/R. AS R↑, I↓
.ALITYPROPORTIONFORSYMBOLAIS
POWER,CURRENT, RESISTANCE, VOLTAGE WHEEL
ANY VARIABLE ON THE POWER WHEELCAN BE FOUND USING THE FOLLOWINGTWO EQUATIONS.
1. V=IR2. P=IV
EXAMPLE: P=V²/RWHERE DID THIS COME FROM?SOLVE EQ. 1. FOR I
V=IR
V/R=IR/R
I=V/R
SUBSITUTE I=V/R INTO EQ. 2
P=IV
P=(V/R)V =V²/R
P=V²/R
DERIVE P=I²R FROM EQUATIONS 1. AND 2.
P=IV SUB. FOR V=IR IN P=IV
P=I(IR)
P=I²R
ONE MORE TO TORTURE YOU!!!
PRV
PRV
PRV
RVPVVV
RVPV
IRV
PRV
2
2
)/(
)/(
SOLVE
SUB. FOR I=V/R
There are two types of energy: potential or stored energy, and kinetic or energy in motion.
Potential energy is stored, or latent. Energy can be stored in many ways
Kinetic energy is actual energy in motion. Moving water, wind, and solar radiation are examples of kinetic energy.
JOULE: UNIT OF ENERGY,TOO SMALL FOR PRACTICAL USE. WATTS ARE USED INSTEAD, MORE ON THIS LATER.
P-2
http://www.youtube.com/watch?v=sSVI5l-MbMQ&list=UU2bkHVIDjXS7sgrgjFtzOXQ
Copper: The Miracle Metal
P-6
ATOMIC STRUCTURE OF ALUMINUM ATOMIC STRUCTURE OF COPPER
ELECTROSTATIC PRECIPITATOR
DUST PARTICLES IN
NEGATIVE CHARGE PLACEDON DUST BY GRID
DUST REMOVED FROM AIRBY ELECTROSTATIC ATTRACTIONWITH THE POSITIVELY CHARGEDPLATES
Electrostatic Precipitator System Working.avi
http://www.youtube.com/watch?v=A0tDieiia_c