Файл: ГДЗ. Физика 9кл_Перышкин_Гутник_2001.pdf

4.

vx

5

-5

5

10

t

5. >ey l_eZ,Z

f k2 ^ey l_eZ,,Z

f k2.

MijZ`g_gb_

1.

>Zgh

J_r_gb_

t = 5 c

t + axt

2

2

2

Z

f k2

s

= v

0

f k k

0,5

(5 )

=

o

x

2

2

v0o

df q f k

f

GZclb sx.

Hl\_l sx

f

2.

>Zgh

J_r_gb_

t = 20 c

t + axt

2

; ao = − v0x

s

t − v0x t

2

Z

f k2

s

= v

0

= v

0

= v0x t =

o

x

2

t

x

2t

2

v0o

f k

f k

k

f

GZclb sx.

Hl\_l sx

f

MijZ`g_gb_

1.

>Zgh

J_r_gb_

s3

f

s1 : s2 : s3 = 1 : 3 : 5; s1 : 2 f = 1 : 5 s1 = 2

5 = 0,4 f;

t1

k

at

2

a =

2s

2

0,4

2

1

1

s1 =

2

t12

=

(1

)2

= 0,8 f/k

.

GZclb s1, a.

Hl\_l s1

f a

f k2.

2.

>Zgh

J_r_gb_

s5

f

s1 : s2 : s3 : s4 : s5 = 1 : 3 : 5 : 7 : 9; s1 : 6,3 f = 1 : 9

t1

k

s1 = 6,3

5 = 0,7 f;

t5

k

at

2

a =

2s

2

0,7

2

1

1

s1 =

2

t12

=

(1

)2

= 1,4 f/k

;

v5

= at5

f k2

k

f k

GZclb v5.

Hl\_l v5

f k

41

1.

f k

2.

G_l ihkdhevdm b

^_j_\h b \hdaZe

`_kldh

k\yaZgu k ^jm]hc

kbkl_fhc hlkq_lZ²A_fe_c

3.

Ijb mkeh\bb g_ih^\b`ghklb wlbo l_e hlghkbl_evgh ^jm] ^jm]Z

4.

df q f k

>Zgh

J_r_gb_

5*.

v1

df q

f k

v\ = v1 + v2

f k f k

f k

v2

f k

va = v2 – v1

f k ±f k

f k

GZclb v\, va.

Hl\_l v\

f k va f k

MijZ`g_gb_

AZdhg bg_jpbb \uihegy_lky \ kbkl_f_ hlkq_lZ k\yaZgghc k A_fe_c b

\ kbkl_f_

hlkq_lZ k\yaZgghc

k

ih_a^hf

\h \j_fy _]h

ijyfhebg_cgh]h b jZ\ghf_jgh]h ^\b`_gby g_

\uihegy_lky \

kbkl_f_ hlkq_lZ k\yaZgghc k ih_a^hf \h \j_fy _]h lhjfh`_gby

Bg_jpbZevghc kbkl_fhc fh`gh kqblZlv a_fex Z ih_a^²g_evay

MijZ`g_gb_

>Zgh

J_r_gb_

1.

Z

f k2

Ih hfm aZdhgm GvxlhgZ

m

d]

F = ma

d] f k2 G

GZclb F.

Hl\_l F

G

>Zgh

J_r_gb_

2.

t = 20 c

F = ma ²hc aZdhg GvxlhgZ

v

f k

v

F

mv

1,84 10

5

4

m

l 105 d]

a =

=

=

=

G

dG

20

t

t

GZclb F.

Hl\_l F dG

>Zgh

J_r_gb_

3.

m1 = m2

Ih hfm aZdhgm GvxlhgZ

a1

f k2

F1 = m1a1; F2 = m2a2. L d m1 = m2 lh ihemqZ_f

a2

f k2

F1

=

F2

F =

a2 F 1

=

0,64

2

1,2

= 9,6 H.

F1

= 1,2 H

2

2

a1

0,08

GZclb F2.

Hl\_l F2 G

a1

a2

42