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TRANSCRIPT
-
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.
(>1.7 x 1011 Pa)
...
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:
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.
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F
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A
F
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FK:
A
F
FK
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H F
A
.
A ,
3 ,
, ,
.
-
.
, .
S.I. 1 Pascal = 1 Pa = 1 N/m2
: F
A
:
A
Fp
: ApF
-
(Pa)
2 1016
4 1011
1,5 1010
1,1 108
1 106
1 2 105
1 105
1 1,6 104
1, 2 30
1, 2 3 10-5
10-12
1 2 1000Hz
-
1 atm = 1.01 x 105 Pa
1 Torr = 1 mm Hg (1 atm = 760 mm Hg)
1 Bar 1 =
= 106 dyn/cm2 (C.G.S.)
1 = 10-3 Torr :
1
-
A
V = A h m = A h
p
p0
F2
F1
W
A
A
h
h0
: F1= p1 A F2 = p2 A
p2 = p1 + p
W = m g = g V = g h p2 p1 = p = - g h
T ,
g
.
H
021 WFF
-
,
.
p0 h=0,
p -h :
p = - gh :
p
p
-h
00
dhgdp -= p-p0=gh
p = p0+gh
gh
2
h = 0
- h
h > 0
-
0
20000
40000
60000
80000
100000
120000
0 100 200 300 400 500
(m)
(Pa)
water
gas(d=10^-3w)
-
water_vs_air.xls
-
.
T,
,
:
pV nRTm
M RT
V n
R (= 8,3145 J/mol K)
: m
V
M
RTp
-
dp = - gdh
dpgM
RTpdh
dp
p
gM
RTdh
p , h = 0, :
dp
p
gM
RTdh
p
p
o
h
o
p p expgM
RTho { }
. h
-
3
-
h
30 km 9.5 torr 25 torr
60 km 0.21 torr .8 torr
90 km 0.0019 torr .03 torr
0
0,2
0,4
0,6
0,8
1
1,2
0 2 4 6 8 10 12 14 16 18 20
Km
Atm
movies/aspirate.mov
-
1 m
.
.
;
() 10.000 kg.
() 1000 kg.
() 100 kg.
() 1 kg.
-
20cm 6m.
p
;
, L = 6m .
:
gLpp 0
4
-
PamsmmKggLppp 4230 109.5)0.6)(/8.9)(/1000(
, 0.6 atm,
.
. ,
p. 6m
, p
p0.
, p :
:
.
-
,
,
.
.
() 13,2
kPa ( / ,
120/80, , 100 mm Hg),
(1,3 m
) (0,5 m ).
5()
-
:
,
:
, 26,7 kPa (
, , , 200 mm Hg).
, ,
, :
8,0 kPa ( 61 mm Hg).
;
-
() ,
,
,
;
( 25
cm );
5()
-
:
a, g
, . (a + g).
[ (a + g)V.]
,
:
1,27 m .
:
,
:
hgahg )(
-
:
h = 0,25 m a, :
,
.
-
'O ,
, . H
, ,
. T .
:
. A
.
movies/HydrostaticParadox.mov
-
U :
x . l =
135 mm d = 12.3 mm.
;
(6 )
-
pint
pint
.
glpp 0int
)(0int dlgpp x
3/916 mKgdl
lx
:
p0 g.
-
TORRICELLI
, , ,
. , ,
, ,
76 cm 760 mm.
, 1644
(Hg) ; Hg =13,6 x 103 Kg/m3 = 10
3 Kg/m3
movies/VacuumFlash7.swfmovies/AirPressureonColumnofH2O.mov
-
TORRICELLI
: Hg =13,6 x 103 Kg/m3 = 10
3 Kg/m3
7
Torricelli ;
mmhh
hghgpatm
336,1076,06,13
movies/Siphon.mov
-
PASCAL
,
g , , ,
,
dp .
p,
' ,
. T Pascal.
-
: 1.
movies/BPascal.mov
-
: 2.
8 9
-
, 2 cm3, ,
( ) .
:
( ),
( ).
-
,
, .
20
.
-
,
.
,
( ) .
-
120 mm Hg .
; ,
, (
)
.
.
-
1,5 x 105 .
. 25
30
.
.
movies/aspirate.movmovies/AirPressureonColumnofH2O.mov
-
h
F2
F1
FB = F1 F2
W W
A
h A
. H
, ,
. 'E
:
F1 = p1 A F2 = p2 A
H F2 ,
F1, ,
.
:
FB = F2 - F1 = (p2 - p1) A
.
'O ,
h 100m:
p2 - p1 = gh
-
FB = g h A = g V
g V. = m_. g:
. T
A,
.
10
-
D ,
0 F0.
2D,
:
() 0 F0
() 0 2F0
() 20 F0
() 20 2F0
-
movies/ArchimedesPrinciple.mov
-
:
() .
()
.
() .
()
.
() .
200
50 .
(/).
-
.
,
-
1
917 kg/m3
1024 kg/m3.
917/1024 =
89.6%
.
2
.
.
.
3
Diet Coke
Classic Coke , Classic
Coke 11
Diet Coke
.
.
movies/FloatingCokeCan.mov
-
;
(
,
)
;
-
-
:
(Body Mass Index BMI) = (kg) / 2 (m2).
( = 30).
(900 kg/m3),
(
1.100 kg/m3).
-
,
.
,
.
,
40%, .
.
(
)
1%.
-
4:
938 kg/m3
. ( = 855
kg/m3 ) .
;
W = B V g = V g L S = d S d = L /
:
.
:
-,
.
. , , .
Pascal.
LdSdLSdSLgVgVgVBBWa
aaaaa
)(
movies/InterfaceFloating.mov
-
: (He) R = 12m m = 196 Kg.
; (: He = 0.16 Kg/m3 = 1.25 Kg/m
3
, ,
He :
B = W = W = V g WHe = He V g
V = 4R3/3
, , :
34 ( ) 76903
He
a a He
B W W mg Mg
M R m Kg
-
( = 900 kg/m
3) R = 2.0m H
= 20cm . = 1030 kg/m3.
() =50 m=5 kg,
. h
(i) (ii)
.
() , .
500 cm3 .
;
-
(i)
FB = W
cmh
mhHmkg
mkg
RH
RhH
V
VgVgV
5,2
2,01030
900
/1030
/900)(3
3
2
2
(ii) .
cmR
mNVHh
mVmR
RhH
mNVVgmNgVgV
WWF NB
6,0...
)514,2()57,12(
)(
2
322
2
-
() , .
500 cm3 .
;
V' , V' = V. :
392,1 mV
mNVgmNgVgV
WWF NB
V - V' = 2,514 1,92 0,6 m3 = 6 x 105 cm3 :
dayshht
hcmt
VQ
501200105
106
/500
2
5
3
-
.
;
() .
() .
() .
()
.
-
4 m 4 m 0,3 m,
.
() 600 kg/m3,
.
() 670
;
-
10cm
2cm ( ).
650 kg/m3 (g = 9,8 m/s2). )
; )
; ) ;
p = g 2cm
= 650 9,8 0,02 Pa = 127,4 Pa
( = 1000 kg/m3)
p = g 10cm + g 2cm
= 833 Pa
W = B +
m g = g Vv + g V
V = 2100cm3
V = 8100cm3
, m = 0,72 kg