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2. m = 0,5 3,5 , -

: 3t5 8t 2. -

, t = 4 . [0,94 .]

4.2.3 .

1 ( 1)

m = 400 -

R = 18 = 1,62 . -

,

, ,

.

:		:
m = 400 = 0,4
r = 0,18	:
= 1,662	I mr2 0,4 0,182 12,96 10 3 2).
I — ? L — ?	-
	:
	L r		m ,

L rm sin rm ,

L 0,18 0,4 1,62 11,66 10 2 2/c).

L

. -

( . 3.21).

: I = 12,96×10-3 3; L =11,66×10-2 2 .

. 3.21

2 ( 2)

, .

, m . -

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,

.

:

M 3m

r1 R r2 R 2

2 — ?

1

. 3.22

:

« » -

: , -

; ,

. -

. ,

« »

.

I1 1 I2 2 ,

I1 1 — ,

r1 R ,

I2 2 —

r2 R . -

2

.

I	1		1	MR 2			mr 2				3	mR2 mR2 2,5mR 2 .
		2					1			2
				I	2			1	MR 2 mr 2				1,75mR2 .
							2			2

:

2,5mR2 1 1,75mR2 2 .

2 2,5 1,43.1 1,75

: 2 1,43 1 .

2

1. D = 0,8

m1 = 6 m2 = 60 . -

,

m 0,5 ? — -

r = 0,4 . = 5 . [0,1 .]

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182

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2. m

w

o

w. .

= 0,1 0

, -

c

A B BYY

. L

,

. .

	m 03 cos sin2
[ L		].

2g

4.2.4.

.

1 ( 1).

m = 10

F = 30 . t = 4c

.

:

:

m = 10

F = 30

, W

I 2

.

t = 4 c

k

2

Wk ?

, -

I

1

mR2 .

2

-

t .

M

.

I

M FR .

,

W

I 2t 2

M 2t 2

F 2t 2

.

k

2

2I

m

900 16

W

1440 ( ).

k

10

: Wk = 1440 .

183

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w. .

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m = 0,3 r = 4 -

, , ,

4t 4 5 . -

t1 = 3,0

t2 = 3,5 ?

: m = 0,3 r = 0,04

4t 4 5

t1 = 3,0 t2 = 3,5 .

A — ?

:

-

.

		I 2		I
	A	2		1	.
		2		2

I 2 mR2 , —

5

, .

— .

d 16t3 . dt

1(t1) =16 × 33 = 432 ( )

2 (t2 ) = 16 × 3,53 = 686 ( )

I 0,4 0,3 0,042 19,2 10 5 2).

:

A 19,2 10 5 (6862 4322 ) 27,26 ( ). 2

: A = 26,27 .

1

1.-

1,5 . ,

= 100. [S = 99,1 ].

2.,

, n = 5 /c, Wk = 60 .

. [L = 3,8 · 2 .]

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3. , -

, . -

0,5 , .

,

	. [	2mgh		,	3,13 ( /c).]
		m	I
			R2

4.3

4.3.1

»

, ,

1. — , -

, -

, :

Mî r		F .

2. ZZ — (

) :

M ZZ (MO )ZZ .

3.ZZ —

,

:

IZZ mr2 .

4. ZZ — ,

, ,

:

I ZZ mi ri2 . i

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5.

( )

A BBYY

c

m R , -

:

1

IZZ

mR2 .

2

m ,

l ,

:

IZZ 1 ml 2 .

12

m , R

, :

IZZ 2 mR2 .

5

6.. -

IZZ

CC , ZZ , -

m a :

IZZ ICC ma2 .

7.

. , -

, , -

, -

:

	N
	M
	i 1	ZZ i
			.

IZZ

—, -

, ,

:

Lî	r	p .

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9. ZZ	w										m
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			—

( ) -

, :

LZZ (Lî )ZZ .

10.

ZZ — , N

, , :

N

LZZ LZZ i . i 1

11. ,

:

LZZ IZZ .

12. . -

N

LZZ i const .

i1

13., -

:

Wk IZZ 2 .

2

, -

, , -

. -

-

.

, -

, ,

, ( 3.23). -, , m0 , -

« » .

187

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. 3.23

mî m1,

.

, ,

:

(m0 m1 ) g		Fh1		(m0 m1 )a1 ,
mo g	Fho moao .

(1)

(2)

-

:

M M òð I ,	(3)

I — ; —

; M — ,

, , -

; M òð —

.

.

(1),(2) (3) OY OX -

:

(mo m1)g Fh1 (mo m1)a1,	(1')
mo g Fho mo ao ,	(2')
M M òð I .	(3')
,
Fho Fh1 ( Fh0	Fh1 )

.

188

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. (

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A B BYY

) :

M (Fh1 Fh0 )R ,

(4)

R .

a1 a0 a , Fh0 Fh0, Fh1 Fh1 ,

(1') (3'), (4) :

(m1 m0 )g Fh1 (m1 m0 )a ,

(5)

m0 g Fh0 m0 a ,

(6)

M M òð I ,

(7)

M (Fh1 Fh0 )R ,

(8)

(5) (6) :

Fh1 Fh0 m1g (m1 2m0 )a .

(9)

a -

:

a .

R

,

a 2l , l — ,

t 2

t . , :
	2l	.	(10)
	t2 R
(9) (10) (8)
:
M (m1g (m1 2m0 ) R)R .			(11)

m1, m2 ,

( m1 2m0 , m2 2m0 M á , Ì á )

M òð .

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, , 1, 2 -

. (11)

m1

M1 (m1g (m1 2m0 1 R)R ,											(12)
					2l		,				(13)
1				Rt2
				1
m2 :
M 2 (m2 g (m2 2m0 ) 2 R)R ,											(14)
2					2l			,			(15)
					Rt22
(3') -
:
M1 M òð I 1 ,											(16)
M 2 M òð I 2 .											(17)
(16) (17) :
I		M 2 M1									(18)
			2
						1
:
M òð	M1 2 M 2 1									.	(19)
			2 1
I M òð ,

(M ) , (3)

( . 3.24), —

1 M 1 M òð .

I I

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