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Βιβλίο Φυσικής Γ' Λυκείου Θετικής Κατεύθυνσης γλώσσα ΕλληνικάGreek Language

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  • 107

  • 108

    4-1

    , . . , , .

    , , - , () , , , .

    -, . - .

    . .

    4-2

    , .

    . - . - .

    . 4.2 . . , . (.4.2).

    . 4.1 - . .

    . 4.2 () - . . () . .

  • 109

    . - .

    - , . - .

    , r = , r .

    - .

    4.3 t1 1 t2=t1+dt - 2=1+d

    t, .

    dtd =

    d 1 rad/s2.

    : (- ) a .

    . .. , . , ( ) . . .

    4.4 . , , , cm(. 4.4) , (. 4.4). - ,

    . 4.3 () d . .

  • 110

    . cm (. 4.4).

    . -

    . 4.2

    . . . . .

    (cm) , - .

    . .. , .

    . 4.4 () () (). - (cm) - ().

    .

    . 4.1 . -.

    .

    . 4.2 - . - .

    .

  • 111

    . , . , , .

    H

    (. 4.5). . , dt ds, ds, d. H cm

    dtds

    cm = (4.1)

    Rdsd = dRds =

    (4.1) dtdRcm

    = , =

    dtd

    ,

    Rcm =

    (. 4.6). , . . cm,

    Rcm = o Rdtd

    dtd cm

    =

    Racm = cma .4-3

    . 4.3 .

    .

    . 4.5 ds, .

    . 4.6 :Racm =

  • 112

    . . (), .

    .

    )

    zz . F .

    F, l ().

    Fl=

    . 1 m.

    . .

    F -, (. 4.9)

    .

    , , . - .

    . 4.7 H - . F .

    . 4.8 F - .

    . 4.9 F Fx l

  • 113

    4.10 F1 F2 . T .

    221121 lFlF =+=

    )

    ' , ( - ). - , - ( ) .

    . , . ( ) - . .

    .

    F

    Fl=

    .

    - F1 F2 . - . d, (. 4.12) x1 F1 x2 F2,

    dFxxFxFxF 12112211 )( =+=+=

    dF 1=

    . , .

    . 4.10 F1 F2. H - .

    . 4.11 .

    4.12 F1 F2 . .

  • 114

    4.1

    4.13 , R1=4 cm R2=3 cm, xx. xx . , F1=6 N F2=10 . .

    . 4.13:

    F1 111 RF= . F2 222 RF= .

    mNRFRF ==+= 06,0221121

    .

    4.2

    4.14 . x1=5 cm x2=8 cm. F1=50 N F2=40 N. F2 = 30 . ;

    :. 4.14

    F1 . NmxF 5,2111 ==

    F2 F2x F2y F2x=F2 30 F2y=F2 30. F2x ( F2x ), F2y

    NmxF 6,1 30 222 == .

    Nm9,021 =+=

    H , .

  • 115

    4-4

    .

    . , , .

    , , . - . . . , , . , , ., ( ).

    -

    0=F 00

    ==

    y

    x

    FF

    0=

    4.3

    l= 4m w1=200N, . x= 1m w2=600 N. ;

    : (w1), - w2 - 1 2 .

    . 4.15

    F=0 1+2-w1-w2=0 (4.2) , . . .

    0= , 02 212= xwlwlT ,

    Nl

    xwlwT 25022 21

    2 =+

    =

    (4.2) NT 5501 =

  • 116

    4-5

    zz(.4.17). m1, m2 . , . m1,m2 , r1, r2

    .

    ....2222

    11 ++= rmrmI 1 kg m2.

    4.4

    , l w=400 N, . . - =30 . .

    :. 4.16

    .x= 30 y= 30

    Fx=0 30=Fx (4.3)

    Fy=0 30 + Fy=w (4.4) 0=

    02

    30 = lwlT (4.5)

    xF Fy xT . (4.5)

    wT = 30 2 NT 400= (4.6) (4.3) (4.6)

    NFx 3200= (4.4) NFy 200=

    F NFFF yx 400)()(22=+=

    33

    ==

    x

    y

    FF

    30=

    . 4.17 To .

  • 117

    .

    - . .

    cmI pI p, d -, , Steiner ().

    cmI , , d o - d.

    2MdII cmp +=

    . 4.18 - d

  • 118

    4.5

    R, .

    :. 4.19

    m1, m2 . m1 + m2 + =M

    R, R .

    2

    212

    22

    12

    222

    11 ...)(...... Rmm Rm Rm rm rmI ++=++=++= 2MRI =

    4.6

    , m1 m2,(m1= m2=m), , l. , - ) ) m1;

    :

    )22

    222

    222

    2

    2

    1mllmlmlmI =

    =

    +

    =

    ) 221 0 mllmI =+=

    . 4.20

    4.7

    , - R, , .

    : . 4.21

    2/2MRIcm = d=R

    23

    2

    22

    22 MRMRMRMdII cmp =+=+=

  • 119

    4-6

    , F m= . . , ' . () ( )

    I= (4.7)

    , ,

    ( ) .

    (4.7) - . , , , . .

    , (4.7) , , , .

    . . , - , .

    - , , .

    . 4.22 , , m .

  • 120

    4.8

    =40 kg R=40 cm, . , F=6 N. , , . ;

    221 MRI = .

    . 4.23

    :

    FR=

    I= 221 MRFR =

    22 /75,0104040

    622 sradmkg

    NMR

    F=

    ==

    4.9

    , R, , , . m. , .

    :

    . m, mg . 4.24

    .

    cmmaTmg = (4.8)

    ( ), F ( ) Mg.

    g F . -

    I= ITR = (4.9)

  • 121

    (4.8) T cmmamgT = (4.9) ImRamgR cm = (4.10) a

    Ra = cma Racm = (4.11) (4.10) ImRmgR = 2

    2mRImgR+

    = (4.12)

    (4.11)

    2

    2

    mRImgRacm+

    = (4.13)

    (4.12) (4.9)

    2mRImgR

    RI

    RIT

    +== 2mRI

    mgIT+

    =

    4.10

    To - , . , , xx. .

    221 mRI = -

    g. .

    : . 4.25

    mg T . :

    cmy maF = cmmaTmg = cmmamgT = (4.14) xx

    I= ITR = (4.15)

    (4.14) (4.15) ImRamgR cm =

    221 mRmRamgR cm = Rag cm 2

    1= (4.16)

    Racm = Racm

    =

    (4.16) cmcm aag 21

    = 3

    2gacm =

  • 122

    4-7

    H . .

    , , , .

    )

    m p - r (. 4.26).

    zz

    rpL = rmL =

    zz . 1kg m2 /s.

    )

    4.27 - zz . . - , , . , m1, m2 . , . , 1111 rmL = ,

    2222 rmL = , . - .

    ... 222111 ++= rmrmL m1, m2 1, 2 11 r = , 22 r = . . .

    ( )... ... 222211222211 ++=++= rm rm rm r mL I rm rm =++ ... 222

    211

    IL = (4.17) - .

    . 4.26 m . .

    . 4.27 m1m2 -.

    . 4.28 - zz . , .

  • 123

    2,71040 kg m2/s 5,81033 kg m2/s (=90km/h) 102 kg m2/s - (33 min) 610-3 kg m2/s 1,0510-35 kg m2/s 0,5310-34 kg m2/s

    - , . , , .

    - , - 0,5310-34 Js.

    !21

    , ! =1,0510-34 J s ( )

    .

    )

    , - -. L1,L2, .., L

    L=L1+L2+

    4.17 dt d, - dIdL =

    IdtdI

    dtdL

    ==

    (4.7)dtdL

    = (4.18)

    ,

    Newton.

  • 124

    O . -, , , .

    . Newton ( - ). . . 4.18

    dtdL

    = (4.19)

    L .

    4-8

    , . .

    ,

    dtdL

    = 0=dtdL

    , , .=L -

    .

    , (), , , . - 24 .

    .

    ewton

    dtdL

    = .

    , .

    .

    . 4.29 -

  • 125

    , ( ), , . :

    2211 II =

    - . 4.4 - , . , , - . , - - , , I . , , I , .

    . , , , , . , . 4.30 , , .

    1,4 2,5 , - pulsars. , , , 15-20 km.

    . 4.4 .

    . 4.30 - .

  • 126

    - - . 3000 . , 25 .

    4-9

    4.11

    4.31, =4 kg. , 1=4rad/s. ; , , , -. ( ) 3,25 kgm2 2,5 kgm2.

    . 4.31

    1 m, 0,2 m . .

    : 1I ,

    , .

    2211111 25,112 mkgMRIIII

    =+=+=

    2I , .

    2222222 82,22 mkgMRIIII

    =+=+=

    , . :

    2211 II = sradII /161

    2

    12 ==

  • 127

    4.32, , zz, .

    ,

    ..., 21 mm

    11 r = , 22 r = , (4.20)

    ,

    ... 21

    21 2

    22211 ++= mmK

    , (4.20)22

    222

    112

    22

    22

    12

    1 ...) ( 21...

    21

    21

    ++=++= rmrmrmrmK

    Irmrm =++ ... 2222

    11

    2

    21IK =

    . - .

    , 4.33 -.

    22

    21

    21

    IMK cm +=

    M cm .

    4-10

    - . . .

    F R, (. 4.35). d

    . 4.32

    . 4.33

  • 128

    dsFdW = dRds =

    dRFdW =

    FR . ddW = (4.21)

    - ... , 21 dd . , 4.35,

    =W

    (4.21)

    dtd

    dtdW

    =

    dtdW / P dtd / ,

    =P

    . , , -

    21

    22 2

    121

    IIW = .

    . 4.34 F d. - F ds=R d.

  • 129

    4.12

    L=0,3 m M, . . ; -

    231 ML

    g=10 m/s2.

    :. 4.35

    . . .

    2LMg

    , 221I , I

    .

    2

    21

    2ILMg = 22

    31

    21

    2MLLMg =

    sradLg / 103 ==

  • 130

    ANI

    4.13

    R . h.H (g) .

    221 MRI = .

    :

    . . , . ,, . , . 4.36

    , Mgh .

    ,

    221

    cmM

    221 I .

    22

    21

    21

    IMMgh cm += 222

    21

    21

    21

    MRMMgh cm +=

    22241

    21

    Rgh cm += (4.22)

    cm Rcm = (4.23)

    (4.22) (4.23)2

    22

    41

    21

    +=R

    Rgh cmcm

    2241

    21

    cmcmgh += ghcm 34

    =

  • 131

    x

    dtdx

    =

    dtd

    =

    dtd =

    dtd

    =

    F

    m

    F m=

    I=

    p=m

    L=I

    ewton

    dtdpF =

    ewton

    dtdL

    =

    F=0 p=

    =0 L=

    2

    21

    mK =

    2

    21IK =

  • 132

    o . dtd

    =

    F, Fl=

    l , - . 1 m.

    F Fl= l , 1 m, .

    0=F 00

    ==

    y

    x

    FF

    0=

    -

    ...2222

    11 ++= rmrmI

    I=

    - -

    prL = rmL = . 1kg m2 /s. - - .

    IL =

    .

    Newton dtdL

    =

    221IK =

    =W

    =P

    To - 21

    22 2

    121

    IIW =

  • 133

    1. .

    . . , . .

    .

    2. .

    . 4.38, . . () - (. 4.38). . . . . .

    .

    0=mgdMgx 0 = mgMg Mm =

    . 4.37

    . 4.38

  • 134

    , - m.

    3.

    , . .

    , :

    , . . ;

    4.1 . 4.40 , , , ;

    4.2 . ;

    4.3 . 4.41 ;)

    t1-t2 .

    . 4.39

    . 4.40

    . 4.41

  • 135

    ) t4 t1.

    ) t1 t4.

    ) t3 t1.

  • 136

    4.4 . - . ) ) ) ) , ;

    4.5 , , - ;

    4.6 . - ; .

    4.7 : , . . .. ..

    4.8 -. ;

    4.9 4.42 . -. - .

    4.10 4.43 - . F1. F2 .) F2; ) F1 F2.

    . 4.42

    . 4.43

  • 137

    4.11 4.44 - . F1 F2 . . - F1 2/3 . F2 ) F1/2 ) 2F1/3 ) F1/3 ) 2F1 ) 3F1/2 ) 3F1 .

    4.12 4.45 m . , ) .) .) .) .

    4.13 , , . ;

    .

    4.14 4.46 zz. . zz.

    4.15 . ;

    4.16 1, 2, 3 4 1,2, 3 4 (.4.47)

    . 4.44

    . 4.45

    . 4.46

    . 4.47

  • 138

    4.17 - )

    .) .) .) . .

    4.18 4.48 -. . 1 2. - . - ; - .

    4.19 4.49 . F . F 4.49

    ;) .) t1 ,

    F .) .) F .

    4.20 (. 4.50). , . ) .) .) .

    . 4.48

    . 4.49

    . 4.50

  • 139

    -

    4.21 , . ;

    4.22 4.51 . , , , . t.

    4.23 )

    .) .) .)

    . .

    4.24 . - . ;)

    .) ) .) .

    4.25 , . ; .

    4.26 . . . . , ; - , , - -. ;

    4.27 1 (. 4.52) , . 2 3 1. - :) ) 2 ) 3 ) /2 ) /3 .

    . 4.51

    . 4.52

  • 140

    4.28 . . . 1. .2.

    .

    4.29 - F :) 1 rad/s 3 rad/s.) 4 rad/s 6 rad/s.) -2 rad/s 5 rad/s.) -3 rad/s 4 rad/s. ;

    4.30 , . - . .

    -

    120 J 40 J 20 J 80 J

    4.31 :

    1 SI rad/s

    rad/s2

    mL

    1 .

  • 141

    4.32 , 4.53. ; 20 rad/s;[: 0,25 rad/s2 , 72 s ]

    4.33 20 m/s. 40 cm. .[: 50 rad/s ]

    4.34 , cmr 40= , 2 m/s2. ;[: 5 rad/s2 ]

    4.35 8cm . 5 m/s. :) .) .[: 10 m/s , 9,9 z ]

    4.36 o , R=20 cm, , =8 m/s. x=20 m. ;[A: 8rad/s2 ]

    4.37 , 20cm. 200. ; ;[ : 40 m ]

    4.38 4.54 R= 0,5 m - . F1=20N F2=30N. - ;[ : 5 m ]

    . 4.53

    . 4.54.

  • 142

    4.39 H 4.55 ' . F1=20N, F2=2N F3=10N. . : x=2 m =30.[ : 16 m ]

    4.40 R1=20 cm, , R2=0,5 m. , ( ) 150 . .[ : 60 ]

    4.41 , l=2 m, - w1=200 w2=300 N (. 4.56). ;[ : 1,2m ]

    4.42 4.57 l=4 m w1=150 N. H 1 m, . w2=700 N. ;[ : 79 cm ]

    4.43 l w1=100 N - (. 4.58). . =30 . w2=40 N. .[ : =180 , F=163,7 N, =0,32 ]

    4.44 (.4.59) . 6m 100kg. . L,

    , 2121 MLI =

    [: 4800 kg m2 ]

    . 4.55

    . 4.56

    . 4.57

    . 4.58

    . 4.59

  • 143

    4.45 , =2 kg R=0,5 m, =100 rad/s F, . 5s. :) () .) F.

    221 MRI = .

    [ : 2/20 srad = NF 10= ]

    4.46 , L=1 m, (.4.60). , , , ;

    2

    31 MLI = g=10 m/s2.

    [ : 15 rad/s2 ]

    -

    4.47 , m=100 g , 4.61. - =16 rad/s, zz. . l=0,8 m.[: 5,12 kg m2/s ]

    4.48 =2 kg R=0,4 m, =10 rad/s . .[ : 3,2 kg m2 ]

    4.49 20 cm 1 kg 2 Hz . 100gr, 10 cm . .

    221 MRI =

    [ : 1,9 Hz ]

    . 4.60

    . 4.61

  • 144

    -

    4.50 =3 kg L=40 cm =10 rad/s . .

    2121 MLIcm = .

    [ : 8 J ]

    4.51 =8 kg R . =5 m/s. - .

    221 MRI = .

    [ : 150 J ]

    4.52 4 m 50 z. ; [ : 400 W ]

    4.53 m=40 kg R=20 cm, 5 z . ) ; ) 5s.

    221 mRI = 102 .

    [: 400J , 80W ]

    4.54 H 4.62 L=2 m = 3kg, . F=10 N . F . :) F, .)

    .)

    ( ) .

    231 MLI = .

    [ : W=40 J, =7,9 rad/s, P=158 W ]

    4.55 H , l=30 cm, (. 4.63). .

    . 4.62

    . 4.63

  • 145

    , .

    12

    2mlI = g=10 m/s2.

    [ : 3 m/s ]

    4.56 l w=100 N 4.64. . =60.

    [ : 3/32 ,750 ,350 === NFNT ]

    4.57 4.65 h R w. F .

    [ : F >hR

    hRhw

    )2(]

    4.58 400 (. 4.66) 30. . .

    [ : 2/3 ]

    4.59 R=0,33 m 1 kg. 100 - . 5 s. -, 0,69. . ( ). [: 1 ]

    4.60 4.67 . L=1 m =0,6 kg. r=0,2 m m=0,1 kg , . f1=10 z. , , . .

    2121 MLI = .

    . 4.64

    . 4.65

    . 4.66

    . 4.67

  • 146

    [ : 5,8 z ]4.61

    5 m/s. 30 . . . ,

    , 252 mR . g=10 m/s2.

    [ : 3,5 m ]

    4.62 30. ,

    , 252 mRI =

    g=10 m/s2. . [ : 25/7 m/s2 ]

    4.63 4.68 m=2 kg R. 1 2 m1=3 kg, m2=1 kg. .

    221 mRI = g=10m/s2.

    .: - . [ : = 4 m/s2 ]

    4.64 . 4.69 200 gr 30 cm 40 rad/s. . 15 cm; ( ).[ : 43,2 J ]

    4.65 O 4.70 0,18 kg m2 =25 rad/s . . .[: 4,5 2 kg m2/s ]

    . 4.68

    . 4.69

    . 4.70

  • 147

    4.66 , 20 cm, - . 20 - . f=4 Hz. .

    221 mRI = . [: 50 kg

    ]

    4.67 . ;

    2

    21 mRI = .

    [: > 3/ ]4.68 m=120

    g R=1,5 cm, (. 4.72). , . )

    , )

    30cm. .

    221 mRI = . g=10 m/s2.

    [: ) 610-3 kg m2/s ) 2 m/s ]

    4.69 m r , , 4.73. , h ; R=20 cm.

    252 mrI = .

    R. [: 54cm ]

    4.70 1 2 , d. 12 , 4.74. , .

    . 4.71

    . 4.72

    . 4.73

    . 4.74

  • 148

    [: g

    d

    2

    2 ]

  • 149

    4.71 m= 2kg (. 4.75). - . . =8,4m/s. . =11,52 kgm2 R=1,2 m.[: 1,75 rad/s ]

    . . ( ) ,

    ABC = .

    C . , () (), . C , . C :

    ( ), C.

    C, - .

    . 4.74

    . 4.76

  • 150

    x, Ay, Az , - Bx, By, z, ,

    zyx

    zyx

    BBBAAAkji

    BAC ==

    i, j k x, y z, .To

    ABBA =

    F

    Fr =(4.24)

    r F. r F .To

    rF= (. 4.77 ) dr = d, F, Fd= (4.25) - F r.

    (4.24) (4.25) - , (4.24) .

    ,

    rprL == m(4.26)

    r . 4-7. (4.26) .

    , , . - . .

    . 4.77

    . 4.78

  • 151

    (4.24) (4.26) . ,

    , . ( Lorentz) :

    F = q

    , - . - . - .

    ()

    . - , -

    ,() .

    - , - .

    - , , - (4000 /min), - 450 km/h. - .

    .

    - ,- , ,

    1 .

    1 .

    . 4.79

  • 152

    .

    . - ( ) (. 4.80). , ( -) .

    , 1 1 - (. 4.80). 1 ( )1R

    1 ( )1ER . -

    1

    1

    1

    1

    =

    RRE

    1

    1. 1 1 1 (. 4.81).

    , - . , , - . .

    ( )lF = . .

    . 4.80

  • 153

    - .

    , 2 2 (. 4.80).

    12

    2

    2=

    ERR

    . 2

    2 .

    2/3 , - . - . , , - , .. .

    , . - (. 4.80).

    .

    .

    . .

    .4.81

  • 154

    (. 4.82 ) . .

    , - .

    . 4.82