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    1

    PHYSICS CHAPTER 1

    CHAPTER 1:CHAPTER 1:

    Physical quantities andPhysical quantities and

    measurementsmeasurements

    (3 Hours)(3 Hours)

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    PHYSICS CHAPTER 1

    2

    At the end of this chapter, students should be able to:At the end of this chapter, students should be able to: StateState basic quantities and their respective SI units: lengthbasic quantities and their respective SI units: length

    (m), time (s), mass (kg), electrical current (A), temperature(m), time (s), mass (kg), electrical current (A), temperature(K), amount of substance (mol) and luminosity (cd).(K), amount of substance (mol) and luminosity (cd).

    StateState derived quantities and their respective units andderived quantities and their respective units andsymbols: velocity (m ssymbols: velocity (m s-1-1), acceleration (m s), acceleration (m s-2-2), work (J),), work (J),force (N), pressure (Pa), energy (J), power (W) andforce (N), pressure (Pa), energy (J), power (W) andfrequency (Hz).frequency (Hz).

    StateState and convert units with common SI prefixes.and convert units with common SI prefixes.

    Learning Outcome:

    1.1 Physical Quantities and Units (1 hour)

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    PHYSICS CHAPTER 1

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    Physical quantityPhysical quantity is defined as a quantity which can be measuredquantity which can be measured

    using measuring instrument.using measuring instrument.

    It can be categorised into 2 types

    Basic (base) quantityBasic (base) quantity

    Derived quantityDerived quantity

    Basic quantityBasic quantity is defined as a quantity which cannot be derivedquantity which cannot be derived

    from any other physical quantity.from any other physical quantity.

    Table 1.1 shows all the basic (base) quantities.

    1.1 Physical Quantities and Units

    Quantity Symbol SI Unit Symbol

    Length l metre m

    Mass m kilogram kg

    Time t second s

    Temperature T/ kelvin K

    Electric current I ampere A

    Amount of substance N mole mol

    Luminous Intensity candela cdTable 1.1Table 1.1

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    PHYSICS CHAPTER 1

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    Derived quantity Symbol Formulae Unit

    Velocity v s/t m s-1

    Frequency f 1/T s-1 or Hz (hertz)

    Acceleration a v/t m s-2

    Pressure F/A N m-2 or Pa

    (pascal)

    Momentum p m v kg m s-1

    Force F m a kg m s-2 or

    N(newton)

    Work W F s kg m2 s-2 or

    J(joule)

    Power P W/t

    Js-1 or W (watt)

    Table 1.2Table 1.2

    Derived quantityDerived quantity is defined as a quantity that is obtained from thequantity that is obtained from the

    combination of base quantities.combination of base quantities.

    Table 1.2 shows some examples of derived quantity.

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    PHYSICS CHAPTER 1

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    UnitUnit is defined as a standard size of measurement of aa standard size of measurement of a

    physical quantity.physical quantity. Examples :

    1 second1 second is defined as the time required forthe time required for

    9,192,631,770 vibrations of radiation emitted by a9,192,631,770 vibrations of radiation emitted by a

    caesium-133 atom.caesium-133 atom.

    1 kilogram1 kilogram is defined as the mass of a platinum-iridiumthe mass of a platinum-iridiumcylinder kept at International Bureau of Weights andcylinder kept at International Bureau of Weights and

    Measures ParisMeasures Paris.

    1 meter1 meter is defined as the length of the path travelled bythe length of the path travelled by

    light in vacuum during a time interval oflight in vacuum during a time interval of

    1299, 792, 458

    s

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    PHYSICS CHAPTER 1

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    rad = 180o

    1 rad =180

    o

    =57.296o

    The unit of a basic quantity is called base unit.

    additional unit for base unit: unit of plane angle - radian (rd)

    unit of solid angle- steradian (sr)

    The common system of units used today are S.I unit (S.I unit (SystemSystem

    International/metric systemInternational/metric system)) and cgs unit - UK.

    The unit of derived quantity called derived unit

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    PHYSICS CHAPTER 1

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    It is used for represent larger and smaller values.for represent larger and smaller values.

    Table 1.3 shows all the unit prefixes.

    Examples:

    5740000 m = 5740 km = 5.74 Mm

    0.00000233 s = 2.33 106 s = 2.33 s

    Prefix Multiple Symbol

    tera 1012 T

    giga 109 G

    mega 106

    Mkilo 103 k

    deci 101 d

    centi 102 c

    milli 103 m

    micro 106

    nano 109 n

    pico 1012 p

    1.1.1 Unit Prefixes

    Table 1.3Table 1.3

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    PHYSICS CHAPTER 1

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    Table 1.4 shows the conversion factors between SI and British units for

    length and mass only.

    1.1.2 Conversion of Unit

    Length Mass

    1 m = 39.37 in = 3.281 ft 1 kg = 103 g

    1 in = 2.54 cm 1 slug = 14.59 kg1 km = 0.621 mi 1 lb = 0.453 592 kg

    1 mi = 5280 ft = 1.609 km 1 kg = 0.0685 slug

    1 angstrom ( ) = 10 10 m

    Table 1.4Table 1.4

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    PHYSICS CHAPTER 1

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    Solve the following problems of unit conversion.

    a. 15 mm2 = ? m2 b. 65 km h1 = ? m s1

    c. 450 g cm3 = ? kg m3 d. 29 cm = ? in

    e. 12 mi h1 = ? m s1

    Solution :Solution :

    a. 15 mm2

    = ? m2

    b. 65 km h-1 = ? m s-1

    11stst method :method : 65 km h1=

    65103 m1 h

    Example 1.1 :

    1 mm 2=103m 2

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    PHYSICS CHAPTER 1

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    22ndnd method :method :

    c. 450 g cm-3 = ? kg m-3

    65 km h1=65 km1 h

    450 g cm3=450 g1 cm 3 103 kg

    1 g

    1 cm 3

    102

    3

    m

    3

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    PHYSICS CHAPTER 1

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    d. 29 cm = ? in

    e. 12 mi h-1 = ? m s-1

    29 cm=29 cm

    1

    2 .54

    in

    1 cm 12 mi h1=

    12 mi1 h

    1 . 609 km1 mi

    1000 m1 km

    1 h3600 s

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    PHYSICS CHAPTER 1

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    At the end of this chapter, students should be able to:At the end of this chapter, students should be able to: DefineDefine scalar and vector quantities.scalar and vector quantities. PerformPerform vector addition and subtraction operationsvector addition and subtraction operations

    graphically:graphically: commutative rulecommutative rule associative rule, andassociative rule, and distributive ruledistributive rule

    Resolve vectorResolve vectorinto two perpendicular components (2-D) :into two perpendicular components (2-D) :

    Components in the x and y axes.Components in the x and y axes.

    Components in the unit vectors in CartesianComponents in the unit vectors in Cartesiancoordinate.coordinate.

    Learning Outcome:

    1.2 Scalars and Vectors (2 hours)

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    PHYSICS CHAPTER 1

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    At the end of this topic, students should be able to:At the end of this topic, students should be able to: Define and useDefine and use dot (scalar) product:dot (scalar) product:

    and cross (vector) product:and cross (vector) product:

    Direction determined by corkscrew method or right handDirection determined by corkscrew method or right handrule.rule.

    Learning Outcome:

    1.2 Scalars and Vectors (2 hours)

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    PHYSICS CHAPTER 1

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    ScalarScalarquantity is defined as a quantity with magnitudequantity with magnitude only. e.g. mass, time, temperature, pressure, electric current,

    work, energy and etc.

    Mathematics operation: ordinary algebra

    VectorVectorquantityis defined as a quantity with both magnitudequantity with both magnitude

    & direction.& direction.

    e.g. displacement, velocity, acceleration, force, momentum,

    electric field, magnetic field and etc.

    Mathematics operation: vector algebra

    1.2 Scalars and Vectors

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    PHYSICS CHAPTER 1

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    Table 1.6 shows written form (notation) of vectors.

    Notation of magnitude of vectors.

    1.2.1 Vectors

    Vector ALengthLength of an arrow magnitudemagnitude of vector A

    displacement velocity acceleration

    s v as av

    v=v

    a=a

    s (bold) v (bold) a (bold)

    DirectionDirection of arrow directiondirection of vector A

    Table 1.6Table 1.6

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    PHYSICS CHAPTER 1

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    Can be represented by using:

    a)a) Direction of compassDirection of compass, i.e east, west, north, south, north-east,

    north-west, south-east and south-west

    b)b) Angle with a reference lineAngle with a reference line

    e.g. A boy throws a stone at a velocity of 20 m s-1, 50 above

    horizontal.

    1.2.2 Direction of Vectors

    50

    v

    x

    y

    0

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    PHYSICS CHAPTER 1

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    c)c) CartesianCartesian coordinates

    2-Dimension (2-D)

    s=x , y =1 m, 5 m

    s

    y/m

    x/m

    5

    10

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    PHYSICS CHAPTER 1

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    3-Dimension (3-D)

    s

    2

    3

    4

    s=x , y , z=4, 3, 2 my/m

    x/m

    z/m

    0

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    PHYSICS CHAPTER 1

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    d)d) PolarPolarcoordinates

    e)e) DenotesDenotes with + or signs+ or signs.

    F=30 N,150

    F150

    +

    +-

    -

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    PHYSICS CHAPTER 1

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    There are two methods involved in addition of vectors graphically i.e.

    ParallelogramParallelogram TriangleTriangle

    For example :

    1.2.3 Addition of Vectors

    ParallelogramParallelogram TriangleTriangle

    BA

    B

    A

    AB

    O

    AB

    B

    A

    AB

    O

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    PHYSICS CHAPTER 1

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    Triangle of vectors method:

    a) Use a suitable scale to draw vector A.

    b) From the head of vector A draw a line to represent the vector B.

    c) Complete the triangle. Draw a line from the tail of vector A to the

    head of vector B to represent the vectorA + B.

    A

    B=

    B

    A

    Commutative RuleCommutative Rule

    B

    A

    BAO

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    PHYSICS CHAPTER 1

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    If there are more than 2 vectors therefore

    Use vector polygon and associative rule. E.g. PQR

    RQP

    R

    Q

    P PQ

    P

    Q

    R=

    P

    Q

    R Associative RuleAssociative Rule

    PQ R

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    PHYSICS CHAPTER 1

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    Distributive Rule :

    a.

    b.

    For example :

    Proof of case a:Proof of case a: let = 2

    AB = A BA= AA

    , are real number

    AB =2 AB

    B

    A

    AB

    O 2 AB

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    PHYSICS CHAPTER 1

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    2 AO

    2 B

    2 A2 B

    2 AB =2 A2 B

    A B=2 A2 B

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    PHYSICS CHAPTER 1

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    Proof of case b:Proof of case b: let = 2 and = 1

    A

    A= 21 A=3 A

    3 A

    AA=2 A1 A2 A A

    3 A

    =

    21 A=2 A1 A

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    PHYSICS CHAPTER 1

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    For example :

    1.2.4 Subtraction of Vectors

    ParallelogramParallelogram TriangleTriangle

    DC

    O

    C D

    O

    D

    C D=C D C

    D

    C

    D

    C

    DC

    D

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    PHYSICS CHAPTER 1

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    Vectors subtraction can be used

    to determine the velocity of one object relative to another object

    i.e. to determine the relative velocity. to determine the change in velocity of a moving object.

    1. Vector A has a magnitude of 8.00 units and 45 above the positive x

    axis. Vector B also has a magnitude of 8.00 units and is directed alongthe negative x axis. Using graphical methods and suitable scale to

    determine

    a) b)

    c) d)(Hint : use 1 cm = 2.00 units)

    Exercise 1.2 :

    AB AB

    A2

    B 2

    A

    B

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    PHYSICS CHAPTER 1

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    11stst methodmethod :

    1.2.5 Resolving a Vector

    R

    Ry

    Rx

    0x

    y

    Rx

    R=cos Rx= R cos

    Ry

    R=sin Ry= R sin

    22ndnd methodmethod :

    R

    Ry

    Rx

    0x

    y

    Rx

    R=sin Rx= R sin

    Ry

    R=cos R

    y= R cos

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    PHYSICS CHAPTER 1

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    The magnitude of vectormagnitude of vectorR :

    Direction of vectorDirection of vectorR :

    VectorR in terms of unit vectors written as

    R orR=Rx 2Ry 2

    tan=R

    y

    Rx

    or=tan1RyR

    x

    R=RxiR

    yj

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    PHYSICS CHAPTER 1

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    A car moves at a velocity of 50 m s-1 in a direction north 30 east.

    Calculate the component of the velocitya) due north. b) due east.

    Solution :Solution :

    Example 1.6 :

    N

    EW

    S

    vN

    vE

    v30

    60

    a)

    b)

    vN= v cos30

    orvN= v sin60

    vE= v sin30

    or

    vE= v cos60

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    PHYSICS CHAPTER 1

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    A particle S experienced a force of 100 N as shown in figure above.

    Determine the x-component and the y-component of the force.

    Solution :Solution :

    Example 1.7 :

    150

    F

    Sx

    15030

    F

    Sx

    y

    Fy

    Fx

    Vector x-component y-component

    Fx=Fcos30

    orFFx=Fcos150

    Fy=Fsin 30

    Fy=Fsin150

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    PHYSICS CHAPTER 1

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    The figure above shows three forces F1, F2and F3 acted on a particle O.

    Calculate the magnitude and direction of the resultant force on particle

    O.

    Example 1.8 : y

    30o

    O

    F230N

    F110N

    30o x

    F340N

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    PHYSICS CHAPTER 1

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    30o

    Solution :Solution :

    O

    y

    x

    F3

    30

    o

    F3y

    Fr= F=F1F2F3Fr= Fx Fy

    Fx=F1xF2xF3x

    Fy=F1yF2yF3y

    F2x

    F1

    F2

    60o

    F2

    F3x

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    PHYSICS CHAPTER 1

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    Solution :Solution :

    Vector x-component y-component

    F1

    F3

    F2

    F1x=0 NF

    1y=F

    1F

    1y=10 N

    F2x=30cos60

    F2x=15 N F

    2y=30sin60

    F2y=26 N

    F3x=40cos30

    F3x=34 .6 N

    F3y=40sin30

    F3y=20 N

    VectorVector

    sumsum

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    PHYSICS CHAPTER 1

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    y

    xO

    Solution :Solution :

    The magnitude of the resultant force is

    and

    Its direction is 162162 from positive x-axis OR 18from positive x-axis OR 18 above negative x-axis.above negative x-axis.

    Fr=Fx

    2Fy2

    =tan1FyFx

    Fy

    Fx

    162

    Fr

    18

    PHYSICS CHAPTER 1

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    PHYSICS CHAPTER 1

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    1. Vector has componentsAx = 1.30 cm,Ay = 2.25 cm; vector

    has componentsBx = 4.10 cm,By = -3.75 cm. Determine

    a) the components of the vector sum ,

    b) the magnitude and direction of ,

    c) the components of the vector ,

    d) the magnitude and direction of . (Young & freedman,pg.35,no.1.42)

    ANS. : 5.40 cm, -1.50 cm; 5.60 cm, 345ANS. : 5.40 cm, -1.50 cm; 5.60 cm, 345; 2.80 cm, -6.00 cm;; 2.80 cm, -6.00 cm;6.62 cm, 2956.62 cm, 295

    2. For the vectors and in Figure 1.2, use the method of vector

    resolution to determine the magnitude and direction of

    a) the vector sum ,

    b) the vector sum ,

    c) the vector difference ,

    d) the vector difference .(Young & freedman,pg.35,no.1.39)

    ANS. : 11.1 m sANS. : 11.1 m s-1-1, 77.6, 77.6; U think;; U think;28.5 m s28.5 m s-1-1, 202, 202; 28.5 m s; 28.5 m s-1-1, 22.2, 22.2

    Exercise 1.3 :

    AB

    A

    ABBABA

    B

    A B

    AB

    BAABBA

    Figure 1.2Figure 1.2

    y

    x0

    37.0

    B 18 .0 m s-1

    A 12 .0 m s-1

    PHYSICS CHAPTER 1

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    PHYSICS CHAPTER 1

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    3. Vector points in the negativex direction. Vector points at an

    angle of 30 above the positivex axis. Vector has a magnitude of

    15 m and points in a direction 40 below the positivex axis. Giventhat , determine the magnitudes of and .(Walker,pg.78,no. 65)

    ANS. : 28 m; 19 mANS. : 28 m; 19 m

    4. Given three vectorsP,Q andR as shown in Figure 1.3.

    Calculate the resultant vector ofP,Q andR.

    ANS. : 49.4 m sANS. : 49.4 m s22; 70.1; 70.1 above + x-axisabove + x-axis

    Exercise 1.3 :

    C

    A

    BABC=0 A

    B

    Figure 1.3Figure 1.3

    y

    x0

    50R 10 m s2

    P35 m s2 Q 24 m s2

    PHYSICS CHAPTER 1

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    PHYSICS CHAPTER 1

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    notations

    E.g. unit vectora a vector with a magnitude of 1 unit in the direction

    of vectorA.

    Unit vectors are dimensionless.

    Unit vector for 3 dimension axes :

    1.2.6 Unit Vectors

    A

    a

    a ,b , c

    a=

    A

    A=1

    [ a ]=1

    y axis j @ j bold i=j=k=1xaxis i@ i bold

    z axisk @ kbold

    PHYSICS CHAPTER 1

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    PHYSICS CHAPTER 1

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    Vector can be written in term of unit vectors as :

    Magnitude of vector,

    x

    z

    y

    kji

    r=rx iry jrzk

    r=rx 2 ry 2rz 2

    PHYSICS CHAPTER 1

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    PHYSICS CHAPTER 1

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    E.g. : s=4 i3 j2 k m

    3 j

    x/m

    y/m

    z/m

    0

    s4 i2 k

    PHYSICS CHAPTER 1

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    PHYSICS CHAPTER 1

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    Two vectors are given as:

    Calculate

    a) the vector and its magnitude,

    b) the vector and its magnitude,

    c) the vector and its magnitude.

    Solution :Solution :

    a)

    The magnitude,

    Example 1.9 :

    ba

    a=i2 j6 k m

    ab

    b=4 i3 j k m

    abx=axbx=14=5 iab

    y

    =ay

    by

    =23=5 j

    abz=azbz=61=7 k

    2ab

    PHYSICS CHAPTER 1

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    PHYSICS CHAPTER 1

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    b)

    The magnitude,

    c)

    The magnitude,

    bax=bxax=41=3 i

    ba y=byay=3 2 =jba z=bzaz=16=5 k

    2ab x=2axbx=2 1 4=6 i

    2ab y=2ayby=2 2 3 =7 j2abz=2azbz=2 6 1=13 k

    PHYSICS CHAPTER 1

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    PHYSICS CHAPTER 1

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    Scalar (dot) productScalar (dot) product

    The physical meaning of the scalar productphysical meaning of the scalar productcan be explained by

    considering two vectors and as shown in Figure 1.4a.

    Figure 1.4b shows the projection of vector onto the direction of

    vector .

    Figure 1.4c shows the projection of vector onto the direction of

    vector .

    1.2.7 Multiplication of Vectors

    A B

    A

    B

    AB

    Figure 1.4aFigure 1.4a

    A

    BA

    B

    B cos

    Figure 1.4bFigure 1.4b

    A

    BAcosFigure 1.4cFigure 1.4c

    ( )BABBA

    toparallelofcomponent=

    ( )ABABA

    toparallelofcomponent=

    PHYSICS CHAPTER 1

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    PHYSICS CHAPTER 1

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    From the Figure 1.4b, the scalar product can be defined as

    meanwhile from the Figure 1.4c,

    where

    The scalar product is a scalar quantityscalar quantity.

    The angle ranges from 0 to 180 . When

    The scalar product obeys the commutative law of multiplicationcommutative law of multiplication i.e.

    AB=A B cos

    : angle between two vectors

    BA=B A cos

    090 scalar product is positivepositive

    90180 scalar product is negativenegative

    =90

    scalar product is zerozero

    AB=BA

    PHYSICS CHAPTER 1

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    PHYSICS CHAPTER 1

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    Example of scalar product is work donework done by a constant force where the

    expression is given by

    The scalar product of the unit vectors are shown below :W=Fs=Fscos =s Fcos

    x

    z

    y

    kji

    ii=i2cos0o=12 1=1

    ii=jj=kk=1

    jj=j2cos0o=12 1 =1

    kk=k2 cos0o=1 2

    1 =1

    ij= 1 1 cos 9 0o=0ij=jk=ik=0

    ik= 1 1 cos 90

    o

    =0

    jk= 1 1 cos 9 0o=0

    PHYSICS CHAPTER 1

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    PHYSICS CHAPTER 1

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    Calculate the and the angle between vectors and for the

    following problems.a) b)

    Solution :Solution :

    a)

    The magnitude of the vectors:

    The angle ,

    Example 1.10 :AAB B

    AB= 1 4 ii1 2 jj1 3 kk

    A=ik A=4 i3 jkB= 4 i2 j3 k B=2 j3 k

    AB=423

    AB=AB cos

    =cos1 ABAB =cos1

    3

    329

    ANS.:ANS.:3; 99.43; 99.4

    PHYSICS CHAPTER 1

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    PHYSICS CHAPTER 1

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    Referring to the vectors in Figure 1.5,a) determine the scalar product between them.

    b) express the resultant vector ofCandD in unit vector.

    Solution :Solution :

    a) The angle between vectors

    Cand

    Dis

    Therefore

    Example 1.11 :

    =18025 19=174

    Figure 1.5Figure 1.5

    y

    x0

    C1 m

    D 2 m 19

    25

    CD=CD cos= 1 2cos174

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    b) Vectors CandD in unit vector are

    and

    Hence

    C=Cx

    iCy

    j

    = 1cos25 i1sin25 j

    C D= 0.911.89 i0.420.65 j

    D=2cos19 i2sin19 j

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    Vector (cross) productVector (cross) product

    Consider two vectors :

    In general, the vector product is defined as

    and its magnitudemagnitude is given by

    where

    The angle ranges from 0 to 180 so the vector product always

    positivepositive value. Vector product is a vector quantityvector quantity.

    The direction of vector is determined by

    B= p iq jrk

    A=x iy jz k

    AB=C

    AB=C=ABsin=AB sin: angle between two vectors

    RIGHT-HAND RULERIGHT-HAND RULE

    C

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    For example:

    How to use right hand rule :

    Point the 4 fingers to the direction of the 1st

    vector. Swept the 4 fingers from the 1st vector towards the 2nd vector.

    The thumb shows the direction of the vector product.

    Direction of the vector product always perpendicularDirection of the vector product always perpendicular

    to the plane containing the vectors andto the plane containing the vectors and .

    A

    C

    BA

    B

    C

    AB=C

    BA=C

    ABBA but AB=BA

    B C

    A

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    The vector product of the unit vectors are shown below :

    Example of vector product is a magnetic force on the straighta magnetic force on the straight

    conductor carrying current places in magnetic fieldconductor carrying current places in magnetic field where the

    expression is given by

    x

    z

    y

    k

    j

    i

    jk=kj=iij=ji=k

    ki=ik=j

    ii=jj= k k=0ii=i2s in 0o=0jj=j 2s in 0o=0

    k k=k2

    s in 0o

    =0

    F=IlB F=IlB sin

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    The vector product can also be expressed in determinant form as

    11stst method :method :

    22ndnd method :method :

    Note :Note :

    The angle between two vectorsThe angle between two vectorscan only be determined by using

    the scalar (dot) productscalar (dot) product.

    AB=i

    j

    kx y z

    p q r

    AB=yrzq ixrzp j xqyp k

    AB=yrzq izpxr j xqyp k

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    Given two vectors :

    Determine

    a) and its magnitude b)

    c) the angle between vectors and .

    Solution :Solution :

    a)

    The magnitude,

    Example 1.12 :

    AB=i

    j

    k3 2 1

    1 0 5

    AB AB

    AB=2 5 1 0 i3 5 1 1 j3 0 2 1 kAB=100 i 151 j 02 k

    A=3 i2 j k

    B=i5 k

    A B

    AB=10 2 16 2 2 2

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    Given two vectors :

    Determine

    a) and its magnitude b)

    c) the angle between vectors and .

    Solution :Solution :

    a)

    The magnitude,

    Example 1.12 :

    AB=i

    j

    k3 2 1

    1 0 5

    AB AB

    AB=2 5 1 0 i3 5 1 1 j3 0 2 1 kAB=100 i 151 j 02 k

    A=3 i2 j k

    B=i5 k

    A B

    AB=10 2 16 2 2 2

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    b)

    c) The magnitude of vectors,

    Using the scalar (dot) productscalar (dot) product formula,

    AB= 3 i2 j ki0 j5 k

    AB=2

    AB= 3 1 ii2 0 jj1 5 kkAB=305

    AB=AB cos

    =cos1 ABAB =cos1 214 26

    A=3 22 2 1 2=14

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    1. If vector and vector , determine

    a) , b) , c) .ANS. :ANS. :

    2. Three vectors are given as follow :

    Calculate

    a) , b) , c) .

    ANS. :ANS. :

    3. If vector and vector ,

    determine

    a) the direction of

    b) the angle between and .

    ANS. : U think, 92.8ANS. : U think, 92.8

    Exercise 1.4 :

    2 k ; 26 ; 46

    a=3 i5 j b=2 i4 jab ab abb

    a=3i3

    j2

    k ; {

    b=

    i4

    j2

    k and { c =2

    i2

    j

    k

    abc abc abc 21;9 ;5 i11 { j9 k

    P=3 i2 jk Q=2

    i4

    j3

    kPQ

    P Q

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    THE END

    Next ChapterCHAPTER 2 :

    Kinematics of Linear Motion

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