Download - Prépa Devoirs n°2
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7/29/2019 Prpa Devoirs n2
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1 (S) m=400g ABCD AB AB=3m CB R=50cm CD CD=2m.
(S) A ) ( .ABC Epp=0 C..1 (S) A, ..2 (S) B..3 (S) C.4. (S) D, CD CD.
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(S)m=200gABCDABAB=2m
CBr =3mCD
(S)AvA=3m.s-1BvB=2m.s-1
OEpp
1(S)AB2f
AB
3. .BCCD3.1.vC(S) C, ..3.2 (S) B, .3.3. (S)vD D.
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.1 ((S m = 0.4Kg ABC AB = 2m BC r = 1m.( ). ((S A .:=60g=10 m.s-2. .AB
1-1 B (Ec(B mgAB.Ec(B).1-2 vB (S) B.1-3 A Ep(A) (S) mgAB
r.Ep(A). .O.2 .BC2-1 vc (S) C vBgr.vC.2-2 (S) CvC = 6.2 m.s-1.
R BC (S) .4
I. ((S B m1=100g Dm=500g R=50cm O. (+).
II.(S) () A. : (S) ():J=2,4.10-3kg.m2.
(S) Epp=0. 0.1 )0( 600 .
1.1. (S) mRgJ( (.2.1 (S) ..3.1 ((S .2. (S) 0=/2 0=4rad/s.
1.2. zmax G.2.2. (S) 0 =3,2rad/s. ((S .
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30
A
B
C D60
(S) O
A BC
D=60
(S)
O
A (S)
rrCB
z
OA
D
B
.O.()
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g=9,8N.kg-1. AB m1=200gm2=100g. () O..OA=0,5L=30cm
-1 G .-2 .3- .
-1.3 .=452.3- .-4 .
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AB m=0,5kg L=18cm () A. ():21 .
3J M l . .:g=9,8N.kg-1
G0 .Epp(G0)=0z=0 0=60 .
1- .-2 :
2
. . 1 cos2 3
m m L LE g
.3- .-4 1 .-5 VB B .
7 . ((S m=300g ((OA((TA
25cm 'm m ( ) O . 0 . 0G .( (1- .:mg-2 .-3 :0
3
.
4- .:g0-5 max . .-6 0.
1.6.0 :max6 . .
.2.6 :2.c ppE E.( ):' 2
3T
mJ
110 .g N Kg
8 .
A 3h m . ( )oz . 1m . 0
ppE 0z..
mE-1 .2-
ppE cE z.
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OA0
A
B0
B
z
()
O
A
B
G
G0 ..
().
.
z
A
Epp=0
O
OI
z
(m)
k
()
z
O
A
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3- ppEmEcE z.-4 . -:-110 .g N Kg .:500m g
9 R . z=h .
.z=0.:g=9,8N.kg-1-1 hge R.2- -3 .eRVsol4- . Vsol .:h=5km.5- ' 100 /
solV m s.
.1.5 ..2.5 .3.5. . :e=1g/cm3 d=1cm.
10 m=0,4kg :
AB- AB=1m =30 .BC- BC=10m =30 .CD- r=0,4m O.OC BC.
ABCD f .BC-1 F F A BVB=4m.s-1.
.1.1 .2.1. .3.1. A B F.
-2 B F BC C VC=1,3m.s-1. B . 1.2. .BC
2.2. .BC3.2.f .f
-3 CD M .1.3. .C2.3. M: .sin cos cos( )ppE mg BC r .3.3. . .
11 (s) m=80g d=100cm l=80cm.
-1 0=60 . ((s mglr. =0. .
2- .-3 .4- .(.g=10(SI
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A
C
M
O
D
z
B
G0
O
G
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1 .:35,0.10k m k( )
2 11 1, 0.10 .C mol l
1 0.5V l 1,3U V 1I A.
1- .2- .3- .-4 k . -5 .:4,0L cm6- 200ml 3 12 15.10 .C mol l .
1.6. .2.6. . :
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3 2 1 3 2 1 3 2 17,1.10 . . ; 7, 4.10 . . ; 7,6.10 . .NO K Cl
S m mol S m mol S m mol
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m=10,1g.1 KNO3 V=500mL (S) C.1.1. C (S)..2.1 .3.1. , aqK )(3 aqNO.
.2 , S = 240mm2 L=1,2cm.
(S) U=0,7V. =40,6mAI.
1.2. .2.2. (S) .3.2. (S) (S.m-1)..4.2 123 ..10.4,7 molmSaqK 123 ..10.1,7)(3 molmSaqNO. :1.14)( molgNM1.16)( molgOM1.39)( molgKM.
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1- C Cm=1,06g/l.2- .-3 25C.-4 C .5-25C . .
.=462mS/m1.5. .2.5. 25C.
25C:2 2 1 2 114,0 . . / / / 7,63 . .Pb Cl
mS m mol mS m mol .
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2013/2014