Механика.Методика решения задач
.pdfȽɥɚɜɚ 1. Ʉɢɧɟɦɚɬɢɤɚ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɢ ɩɪɨɫɬɟɣɲɢɯ ɫɢɫɬɟɦ |
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Ⱦɥɹ ɪɟɲɟɧɢɹ ɡɚɞɚɱɢ ɡɚɩɢɫɚɧɧɵɟ ɭɪɚɜɧɟɧɢɹ ɧɟɨɛɯɨɞɢɦɨ ɞɨɩɨɥɧɢɬɶ ɨɩɪɟɞɟɥɟɧɢɹɦɢ (1.24) ɢ ɜɵɪɚɠɟɧɢɹɦɢ (1.25) ɞɥɹ ɢɧɬɟɪɟɫɭɸɳɢɯ ɧɚɫ ɜɟɥɢɱɢɧ, ɩɪɢɜɟɞɟɧɧɵɦɢ ɜ ɩ. 1.1.
III. ɇɚɣɞɟɦ ɡɚɤɨɧɵ ɢɡɦɟɧɟɧɢɹ ɫɤɨɪɨɫɬɢ ɝɪɭɡɚ ɢ ɟɝɨ ɭɫɤɨɪɟɧɢɹ ɜ ɩɪɨɟɤɰɢɹɯ ɧɚ ɨɫɢ ɞɟɤɚɪɬɨɜɨɣ ɫɢɫɬɟɦɵ ɤɨɨɪɞɢɧɚɬ, ɢɫɩɨɥɶɡɭɹ
ɨɩɪɟɞɟɥɟɧɢɹ (1.6) ɢ (1.12): |
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Xx |
dx |
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2bt , Xy |
0 ; |
(1.82) |
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dt |
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ax |
dX |
2b , ay |
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(1.83) |
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d t |
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Ɍɨɱɤɢ ɨɛɨɞɚ ɜɚɥɚ ɫɨɜɟɪɲɚɸɬ ɧɟɪɚɜɧɨɦɟɪɧɨɟ ɞɜɢɠɟɧɢɟ ɩɨ ɨɤɪɭɠɧɨɫɬɢ, ɩɪɢɱɟɦ ɦɨɞɭɥɶ ɢɯ ɫɤɨɪɨɫɬɢ (ɩɨɫɤɨɥɶɤɭ ɧɢɬɶ ɧɟɪɚɫɬɹɠɢɦɚ ɢ ɧɟ ɩɪɨɫɤɚɥɶɡɵɜɚɟɬ ɩɨ ɩɨɜɟɪɯɧɨɫɬɢ ɨɛɨɞɚ) ɜ ɤɚɠɞɵɣ ɦɨɦɟɧɬ ɜɪɟɦɟɧɢ ɪɚɜɟɧ ɦɨɞɭɥɸ ɫɤɨɪɨɫɬɢ ɝɪɭɡɚ, ɩɨɷɬɨɦɭ, ɢɫɩɨɥɶɡɭɹ (1.22) ɞɥɹ ɭɝɥɨɜɨɣ ɫɤɨɪɨɫɬɢ Z ɢ ɭɝɥɨɜɨɝɨ ɭɫɤɨɪɟɧɢɹ E, ɩɨɥɭɱɚɟɦ:
Z |
Xx |
2bt |
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(1.84) |
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R |
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R |
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E |
d Z |
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2b |
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(1.85) |
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ɉɨɫɤɨɥɶɤɭ ɩɪɨɟɤɰɢɹ ɭɫɤɨɪɟɧɢɹ ɝɪɭɡɚ ɧɚ ɨɫɶ X ɪɚɜɧɚ ɬɚɧɝɟɧɰɢɚɥɶɧɨɣ ɩɪɨɟɤɰɢɢ ɭɫɤɨɪɟɧɢɹ ɬɨɱɟɤ ɨɛɨɞɚ, ɬɨ:
aW |
2b . |
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(1.86) |
ɇɨɪɦɚɥɶɧɭɸ ɩɪɨɟɤɰɢɸ ɭɫɤɨɪɟɧɢɹ ɨɩɪɟɞɟɥɢɦ, ɢɫɩɨɥɶɡɭɹ |
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(1.22): |
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an |
X2 |
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4b2t |
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(1.87) |
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Ɇɨɞɭɥɶ ɩɨɥɧɨɝɨ ɭɫɤɨɪɟɧɢɹ ɩɪɨɢɡɜɨɥɶɧɨɣ ɬɨɱɤɢ A ɧɚ ɨɛɨɞɟ |
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ɤɨɥɟɫɚ ɧɚɣɞɟɦ ɢɡ ɫɨɨɬɧɨɲɟɧɢɹ (1.20): |
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a |
a2 a2 |
2b |
4b2t 4 |
1 . |
(1.88) |
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n |
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Ɂɚɤɨɧ ɞɜɢɠɟɧɢɹ ɩɪɨɢɡɜɨɥɶɧɨɣ ɬɨɱɤɢ A ɧɚ ɨɛɨɞɟ ɜɚɥɚ ɡɚɩɢ- |
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ɲɟɦ ɜ ɩɨɥɹɪɧɨɣ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ: |
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M(t) |
M0 |
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E t 2 |
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M0 |
bt 2 |
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(1.89) |
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2 |
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ɝɞɟ M0 – ɧɚɱɚɥɶɧɨɟ ɡɧɚɱɟɧɢɟ ɭɝɥɨɜɨɣ ɤɨɨɪɞɢɧɚɬɵ ɬɨɱɤɢ A ɜ ɜɵɛɪɚɧɧɨɣ ɩɨɥɹɪɧɨɣ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ.
32 ɆȿɏȺɇɂɄȺ. ɆȿɌɈȾɂɄȺ Ɋȿɒȿɇɂə ɁȺȾȺɑ
Ɂɚɞɚɱɚ 1.9
(ɇɚ ɤɢɧɟɦɚɬɢɤɭ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ)
Ɂɚɤɨɧ ɞɜɢɠɟɧɢɹ ɞɜɢɠɭɳɟɣɫɹ ɜ ɩɥɨɫɤɨɫɬɢ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ, ɡɚɞɚɧɧɵɣ ɜ ɩɨɥɹɪɧɨɣ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ, ɢɦɟɟɬ ɫɥɟɞɭɸɳɢɣ
ɜɢɞ: r = r(t), ij = ij(t). Ɉɩɪɟɞɟɥɢɬɶ ɡɚ- |
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ɤɨɧɵ ɢɡɦɟɧɟɧɢɹ ɩɪɨɟɤɰɢɣ ɫɤɨɪɨɫɬɢ ɢ |
Y |
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ɭɫɤɨɪɟɧɢɹ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɧɚ |
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eM |
er |
ɧɚɩɪɚɜɥɟɧɢɹ, ɡɚɞɚɜɚɟɦɵɟ ɨɪɬɚɦɢ ɞɟ- |
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ɤɚɪɬɨɜɨɣ ɢ ɩɨɥɹɪɧɨɣ ɫɢɫɬɟɦ ɤɨɨɪɞɢ- |
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M |
ɧɚɬ, ɠɟɫɬɤɨ ɫɜɹɡɚɧɧɵɯ ɫ ɬɟɥɨɦ ɨɬɫɱɟ- |
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j |
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ɬɚ. ɇɚɱɚɥɨ ɞɟɤɚɪɬɨɜɨɣ ɫɢɫɬɟɦɵ ɤɨɨɪ- |
M |
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ɞɢɧɚɬ ɫɨɜɩɚɞɚɟɬ ɫ ɩɨɥɸɫɨɦ ɩɨɥɹɪɧɨɣ |
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ɫɢɫɬɟɦɵ, ɚ ɨɫɶ X ɞɟɤɚɪɬɨɜɨɣ ɫɢɫɬɟɦɵ |
O |
i |
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ɧɚɩɪɚɜɥɟɧɚ ɜɞɨɥɶ ɩɨɥɹɪɧɨɣ ɨɫɢ (ɫɦ. |
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Ɋɢɫ. 1.14 |
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ɪɢɫ. 1.14). |
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Ɋɟɲɟɧɢɟ |
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I. ȼɵɛɟɪɟɦ ɨɫɶ Y ɞɟɤɚɪɬɨɜɨɣ ɫɢɫɬɟɦɵ ɤɨɨɪɞɢɧɚɬ ɬɚɤ, ɱɬɨɛɵ ɩɥɨɫɤɨɫɬɶ XY ɫɨɜɩɚɞɚɥɚ ɫ ɩɥɨɫɤɨɫɬɶɸ, ɜ ɤɨɬɨɪɨɣ ɞɜɢɠɟɬɫɹ ɦɚɬɟɪɢɚɥɶɧɚɹ ɬɨɱɤɚ M (ɪɢɫ. 1.14). Ⱦɥɹ ɪɟɲɟɧɢɹ ɡɚɞɚɱɢ ɢɫɩɨɥɶɡɭɟɦ ɞɜɟ ɫɢɫɬɟɦɵ ɤɨɨɪɞɢɧɚɬ – ɞɟɤɚɪɬɨɜɭ ɫɢɫɬɟɦɭ ɤɨɨɪɞɢɧɚɬ XOY c ɨɪɬɚɦɢ i ɢ j , ɢ ɩɨɥɹɪɧɭɸ, ɨɪɬɵ ɤɨɬɨɪɨɣ er ɢ eM ɢɡɨɛɪɚɠɟɧɵ ɧɚ ɪɢɫ. 1.14.
Ɂɚɦɟɬɢɦ, ɱɬɨ ɩɪɢ ɞɜɢɠɟɧɢɢ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɩɪɨɢɫɯɨɞɢɬ ɢɡɦɟɧɟɧɢɟ ɨɪɢɟɧɬɚɰɢɢ ɨɪɬɨɜ ɩɨɥɹɪɧɨɣ ɫɢɫɬɟɦɵ er ɢ eM , ɜ ɬɨ ɜɪɟɦɹ ɤɚɤ
ɨɪɬɵ ɞɟɤɚɪɬɨɜɨɣ ɫɢɫɬɟɦɵ ɤɨɨɪɞɢɧɚɬ i ɢ j ɧɟ ɢɡɦɟɧɹɸɬ ɫɜɨɟɝɨ ɧɚ-
ɩɪɚɜɥɟɧɢɹ.
II, III. Ɂɚɤɨɧ ɞɜɢɠɟɧɢɹ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ, ɡɚɞɚɧɧɵɣ ɜ ɩɨɥɹɪɧɨɣ ɫɢɫɬɟɦɟ, ɡɚɩɢɲɟɦ ɜ ɞɟɤɚɪɬɨɜɨɣ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ XOY:
x(t) r(t) cosM(t),
(1.90)
y(t) r(t)sinM(t).
Ⱦɢɮɮɟɪɟɧɰɢɪɭɹ ɡɚɤɨɧ ɞɜɢɠɟɧɢɹ (1.90) ɩɨ ɜɪɟɦɟɧɢ, ɩɨɥɭɱɚɟɦ ɢɫɤɨɦɵɟ ɡɚɤɨɧɵ ɢɡɦɟɧɟɧɢɹ ɩɪɨɟɤɰɢɣ ɫɤɨɪɨɫɬɢ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ
ɢ ɟɟ ɭɫɤɨɪɟɧɢɹ ɜ ɞɟɤɚɪɬɨɜɨɣ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ: |
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Xx |
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r cosM rM sinM, |
(1.91) |
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y |
r sinM rM cosM; |
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Ƚɥɚɜɚ 1. Ʉɢɧɟɦɚɬɢɤɚ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɢ ɩɪɨɫɬɟɣɲɢɯ ɫɢɫɬɟɦ |
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ax |
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Xx |
(r |
rM |
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rM) sinM, |
(1.92) |
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X y |
(r |
rM |
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rM) cosM. |
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ȼ ɮɨɪɦɭɥɚɯ (1.92), (1.92) ɢ ɞɚɥɟɟ ɞɥɹ ɤɪɚɬɤɨɫɬɢ ɨɩɭɫɬɢɦ ɡɚɩɢɫɶ ɡɚɜɢɫɢɦɨɫɬɢ ɤɢɧɟɦɚɬɢɱɟɫɤɢɯ ɜɟɥɢɱɢɧ ɨɬ ɜɪɟɦɟɧɢ.
ɉɪɨɟɤɰɢɢ ɫɤɨɪɨɫɬɢ ɢ ɭɫɤɨɪɟɧɢɹ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɜ ɩɨɥɹɪɧɨɣ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ ɧɚɯɨɞɢɦ ɞɜɭɦɹ ɫɩɨɫɨɛɚɦɢ.
1 ɫɩɨɫɨɛ. ɋɤɨɪɨɫɬɶ ɢ ɭɫɤɨɪɟɧɢɟ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɜ ɩɨɥɹɪ-
ɧɨɣ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ ɡɚɩɢɫɵɜɚɸɬɫɹ ɜ ɜɢɞɟ: |
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Xr er XMeM , |
(1.93) |
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ar er aMeM . |
(1.94) |
ɋɥɟɞɨɜɚɬɟɥɶɧɨ, ɩɪɨɟɤɰɢɢ ɫɤɨɪɨɫɬɢ ɢ ɭɫɤɨɪɟɧɢɹ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɧɚ ɧɚɩɪɚɜɥɟɧɢɹ, ɡɚɞɚɜɚɟɦɵɟ ɨɪɬɚɦɢ ɪɚɫɫɦɚɬɪɢɜɚɟɦɵɯ ɫɢɫɬɟɦ ɤɨɨɪɞɢɧɚɬ, ɫɜɹɡɚɧɵ ɫɨɨɬɧɨɲɟɧɢɹɦɢ:
Xx |
ȣ i |
Xr er i XM eM i |
Xr cosM XM sin M, |
(1.95) |
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ȣ j |
Xr er j XM eM j |
Xr sin M XM cosM; |
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ax |
a i |
ar er i aM eM i |
ar cosM aM sinM, |
(1.96) |
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a j |
ar er j aMeM j |
ar sin M aM cosM. |
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ɋɪɚɜɧɢɜɚɹ ɫɨɨɬɧɨɲɟɧɢɹ (1.90) ɢ (1.95), ɚ ɬɚɤɠɟ (1.91) ɢ (1.96), ɩɨɥɭɱɢɦ ɢɫɤɨɦɵɟ ɩɪɨɟɤɰɢɢ ɫɤɨɪɨɫɬɢ ɢ ɭɫɤɨɪɟɧɢɹ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɜ ɩɨɥɹɪɧɨɣ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ:
Xr |
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r, |
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rM; |
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ar |
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2rM |
rM. |
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2 ɫɩɨɫɨɛ. Ɂɚɩɢɲɟɦ ɪɚɞɢɭɫ-ɜɟɤɬɨɪ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɜ ɩɨɥɹɪɧɨɣ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ:
r rer . |
(1.99) |
ɉɨɫɤɨɥɶɤɭ ɩɪɢ ɞɜɢɠɟɧɢɢ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɩɪɨɢɫɯɨɞɢɬ ɢɡɦɟɧɟɧɢɟ ɨɪɢɟɧɬɚɰɢɢ ɨɪɬɨɜ ɩɨɥɹɪɧɨɣ ɫɢɫɬɟɦɵ er ɢ eM , ɧɚɣɞɟɦ
ɫɤɨɪɨɫɬɶ ɢɯ ɢɡɦɟɧɟɧɢɹ (ɫɦ. ɪɢɫ. 1.15):
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er |
MeM , |
(1.100) |
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eM |
Mer. |
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34 ɆȿɏȺɇɂɄȺ. ɆȿɌɈȾɂɄȺ Ɋȿɒȿɇɂə ɁȺȾȺɑ
deM |
e |
der |
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Ɋɢɫ. 1.15 |
Ɍɟɩɟɪɶ ɞɥɹ ɧɚɯɨɠɞɟɧɢɹ ɫɤɨɪɨɫɬɢ ɢ ɭɫɤɨɪɟɧɢɹ ɬɨɱɤɢ ɜ ɬɨɣ ɠɟ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ ɧɟɨɛɯɨɞɢɦɨ ɩɪɨɞɢɮɮɟɪɟɧɰɢɪɨɜɚɬɶ ɪɚɞɢɭɫɜɟɤɬɨɪ (1.99) ɩɨ ɜɪɟɦɟɧɢ ɫ ɭɱɟɬɨɦ (1.100):
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(1.101) |
ȣ r |
rer |
rer |
rer |
rMeM |
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a ȣ |
rer |
rer |
rMeM rMeM rMeM |
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2 |
)er |
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(1.102) |
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(r |
rM |
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(2rM |
rM)eM . |
ȼ ɫɨɨɬɜɟɬɫɬɜɢɢ ɫ (1.101) ɢ (1.102) ɢɫɤɨɦɵɟ ɩɪɨɟɤɰɢɢ ɫɤɨɪɨɫɬɢ ɢ ɭɫɤɨɪɟɧɢɹ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɜ ɩɨɥɹɪɧɨɣ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ ɪɚɜɧɵ:
Xr |
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r, |
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(1.103) |
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XM |
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rM |
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ar |
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r rM |
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aM |
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2rM rM. |
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Ʉɚɤ ɜɢɞɢɦ, ɨɛɚ ɫɩɨɫɨɛɚ ɪɟɲɟɧɢɹ ɞɚɸɬ ɨɞɢɧɚɤɨɜɵɣ ɪɟɡɭɥɶɬɚɬ.
Ɂɚɞɚɱɚ 1.10
(ɇɚ ɤɢɧɟɦɚɬɢɤɭ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ)
Ⱦɜɢɠɟɧɢɟ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɜ ɩɨɥɹɪɧɨɣ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ ɡɚɞɚɟɬɫɹ ɜɡɚɢɦɨɫɜɹɡɶɸ ɩɨɥɹɪɧɵɯ ɤɨɨɪɞɢɧɚɬ r(M) 2a(1 cosM) , ɩɪɢ ɷɬɨɦ ɩɨɥɹɪɧɵɣ ɭɝɨɥ ɜɨɡɪɚɫɬɚɟɬ ɥɢɧɟɣɧɨ ɜɨ
ɜɪɟɦɟɧɢ M(t) bt . Ɉɩɪɟɞɟɥɢɬɶ ɡɚɜɢɫɢɦɨɫɬɶ ɦɨɞɭɥɹ ɫɤɨɪɨɫɬɢ ɢ ɦɨɞɭɥɹ ɭɫɤɨɪɟɧɢɹ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɨɬ ɜɪɟɦɟɧɢ.
Ɋɟɲɟɧɢɟ
I. Ɋɟɲɚɟɦ ɡɚɞɚɱɭ ɜ ɡɚɞɚɧɧɨɣ ɩɨɥɹɪɧɨɣ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ. Ɂɚɦɟɬɢɦ, ɱɬɨ ɦɚɬɟɪɢɚɥɶɧɚɹ ɬɨɱɤɚ M ɞɜɢɠɟɬɫɹ ɩɨ ɡɚɦɤɧɭɬɨɣ ɬɪɚɟɤ-
Ƚɥɚɜɚ 1. Ʉɢɧɟɦɚɬɢɤɚ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɢ ɩɪɨɫɬɟɣɲɢɯ ɫɢɫɬɟɦ |
35 |
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ɬɨɪɢɢ, ɩɟɪɢɨɞɢɱɟɫɤɢ, ɫ ɩɟɪɢɨɞɨɦ |
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2S |
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b , ɜɨɡɜɪɚɳɚɹɫɶ ɜ ɬɭ |
ɠɟ |
ɬɨɱɤɭ |
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M |
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ɩɪɨɫɬɪɚɧɫɬɜɚ (ɫɦ. ɪɢɫ. 1.16). |
a(tk ) |
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II. Ɉɩɪɟɞɟɥɢɦ ɡɚɤɨɧ ɢɡɦɟɧɟ- |
M(t) |
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ɧɢɹ ɩɪɨɟɤɰɢɣ ɫɤɨɪɨɫɬɢ ɢ ɭɫɤɨɪɟ- |
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ɧɢɹ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɜ ɩɨɥɹɪ- |
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ɧɨɣ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ, ɜɨɫɩɨɥɶ- |
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ɡɨɜɚɜɲɢɫɶ |
ɮɨɪɦɭɥɚɦɢ |
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(1.104), ɩɨɥɭɱɟɧɧɵɦɢ ɜ ɩɪɟɞɵɞɭ- |
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Ɋɢɫ. 1.16 |
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ɳɟɣ ɡɚɞɚɱɟ: |
2a sinMM |
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(1.105) |
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rM |
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2ab |
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aM |
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Ɍɨɝɞɚ ɢɫɤɨɦɵɟ ɦɨɞɭɥɢ ɫɤɨɪɨɫɬɢ ɢ ɭɫɤɨɪɟɧɢɹ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɪɚɜɧɵ:
X |
X2 |
X2 |
2ab |
2 2 cos(bt) , |
(1.107) |
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M |
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a2 |
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2ab2 |
5 4 cos(bt). |
(1.108) |
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Ɂɚɦɟɬɢɦ, ɱɬɨ ɦɚɬɟɪɢɚɥɶɧɚɹ ɬɨɱɤɚ ɜ ɦɨɦɟɧɬɵ ɜɪɟɦɟɧɢ |
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tk |
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(ɝɞɟ k = 0, 1, 2, ...) ɧɚɯɨɞɢɬɫɹ ɜ ɧɚɱɚɥɟ (ɩɨɥɸɫɟ) ɩɨ- |
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ɥɹɪɧɨɣ ɫɢɫɬɟɦɵ ɤɨɨɪɞɢɧɚɬ, ɢɦɟɟɬ ɧɭɥɟɜɭɸ ɫɤɨɪɨɫɬɶ, ɚ ɭɫɤɨɪɟɧɢɟ, ɩɨ ɦɨɞɭɥɸ ɪɚɜɧɨɟ a(tk ) 2ab2 , ɧɚɩɪɚɜɥɟɧɨ ɩɪɨɬɢɜɨɩɨɥɨɠɧɨ ɩɨɥɹɪɧɨɣ ɨɫɢ.
Ɂɚɞɚɱɚ 1.11
(ɇɚ ɤɢɧɟɦɚɬɢɤɭ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ)
ɉɥɚɧɟɬɚ ɞɜɢɠɟɬɫɹ ɜɨɤɪɭɝ ɋɨɥɧɰɚ ɜ ɫɨɨɬɜɟɬɫɬɜɢɢ ɫ ɡɚɤɨɧɚɦɢ Ʉɟɩɥɟɪɚ ɩɨ ɷɥɥɢɩɬɢɱɟɫɤɨɣ ɬɪɚɟɤɬɨɪɢɢ r(1 e cosM) p . ɉɚɪɚɦɟɬɪ
ɷɥɥɢɩɫɚ p , ɷɤɫɰɟɧɬɪɢɫɢɬɟɬ e ɢ ɫɟɤɬɨɪɧɭɸ ɫɤɨɪɨɫɬɶ V ɫɱɢɬɚɬɶ ɡɚ-
ɞɚɧɧɵɦɢ. Ɉɩɪɟɞɟɥɢɬɶ ɩɪɨɟɤɰɢɢ ɭɫɤɨɪɟɧɢɹ ɩɥɚɧɟɬɵ ɜ ɡɚɜɢɫɢɦɨɫɬɢ ɨɬ ɤɨɨɪɞɢɧɚɬ r ɢ M ɩɨɥɹɪɧɨɣ ɫɢɫɬɟɦɵ.
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ɆȿɏȺɇɂɄȺ. ɆȿɌɈȾɂɄȺ Ɋȿɒȿɇɂə ɁȺȾȺɑ |
Ɋɟɲɟɧɢɟ
I. ɉɪɢ ɪɟɲɟɧɢɢ ɡɚɞɚɱɢ ɛɭɞɟɦ ɫɱɢɬɚɬɶ ɩɥɚɧɟɬɭ ɢ ɋɨɥɧɰɟ ɦɚɬɟɪɢɚɥɶɧɵɦɢ ɬɨɱɤɚɦɢ. ɋɨɝɥɚɫɧɨ ɩɟɪɜɨɦɭ ɡɚɤɨɧɭ Ʉɟɩɥɟɪɚ ɜɫɟ ɩɥɚɧɟɬɵ ɞɜɢɠɭɬɫɹ ɩɨ ɷɥɥɢɩɬɢɱɟɫɤɢɦ ɨɪɛɢɬɚɦ, ɩɪɢɱɟɦ ɋɨɥɧɰɟ ɧɚɯɨɞɢɬɫɹ ɜ ɨɞɧɨɦ ɢɡ ɮɨɤɭɫɨɜ ɷɥɥɢɩɫɚ O (ɫɦ. ɪɢɫ. 1.17).
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rM't |
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r(t+ǻt) |
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O |
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Ɋɢɫ. 1.17 |
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ȼ ɫɨɨɬɜɟɬɫɬɜɢɢ ɫ ɭɫɥɨɜɢɟɦ ɡɚɞɚɱɢ ɜɜɟɞɟɦ ɩɨɥɹɪɧɭɸ ɫɢɫɬɟɦɭ ɤɨɨɪɞɢɧɚɬ ɜ ɩɥɨɫɤɨɫɬɢ ɞɜɢɠɟɧɢɹ ɩɥɚɧɟɬɵ, ɩɨɥɸɫ ɤɨɬɨɪɨɣ ɫɨɜɩɚɞɚɟɬ ɫ ɋɨɥɧɰɟɦ, ɚ ɩɨɥɹɪɧɚɹ ɨɫɶ ɫɨɜɩɚɞɚɟɬ ɫ ɨɞɧɨɣ ɢɡ ɨɫɟɣ ɷɥɥɢɩɫɚ.
ɋɨɝɥɚɫɧɨ ɜɬɨɪɨɦɭ ɡɚɤɨɧɭ Ʉɟɩɥɟɪɚ ɫɟɤɬɨɪɧɚɹ ɫɤɨɪɨɫɬɶ V ɩɥɚɧɟɬɵ, ɪɚɜɧɚɹ ɫɤɨɪɨɫɬɢ ɢɡɦɟɧɟɧɢɹ ɩɥɨɳɚɞɢ, ɨɩɢɫɵɜɚɟɦɨɣ ɪɚɞɢ- ɭɫ-ɜɟɤɬɨɪɨɦ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ, ɩɪɟɞɫɬɚɜɥɹɸɳɢɦ ɩɥɚɧɟɬɭ, ɩɨɫɬɨɹɧɧɚ ɩɪɢ ɞɜɢɠɟɧɢɢ ɩɥɚɧɟɬɵ ɜɨɤɪɭɝ ɋɨɥɧɰɚ.
II. Ⱦɥɹ ɧɚɯɨɠɞɟɧɢɹ ɩɪɨɟɤɰɢɣ ɭɫɤɨɪɟɧɢɹ ɩɥɚɧɟɬɵ ɜ ɩɨɥɹɪɧɨɣ
ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ ɜɨɫɩɨɥɶɡɭɟɦɫɹ ɮɨɪɦɭɥɚɦɢ (1.104): |
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ar |
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r rM |
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aM |
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2rM |
rM. |
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ɉɨɫɤɨɥɶɤɭ ɜ ɭɪɚɜɧɟɧɢɹ (1.109) ɜɯɨɞɹɬ ɩɪɨɢɡɜɨɞɧɵɟ ɩɨɥɹɪɧɵɯ ɤɨɨɪɞɢɧɚɬ ɩɨ ɜɪɟɦɟɧɢ, ɞɨɩɨɥɧɢɦ ɷɬɭ ɫɢɫɬɟɦɭ ɭɪɚɜɧɟɧɢɟɦ ɬɪɚɟɤɬɨɪɢɢ ɩɥɚɧɟɬɵ ɢ ɜɵɪɚɠɟɧɢɟɦ ɞɥɹ ɟɟ ɫɟɤɬɨɪɧɨɣ ɫɤɨɪɨɫɬɢ V :
r(1 e cosM) p , |
(1.110) |
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V |
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2 r M . |
III. ȼ ɫɨɨɬɜɟɬɫɬɜɢɢ ɫ ɭɫɥɨɜɢɟɦ ɡɚɞɚɱɢ ɫɟɤɬɨɪɧɚɹ ɫɤɨɪɨɫɬɶ V ɩɨɫɬɨɹɧɧɚ ɩɪɢ ɞɜɢɠɟɧɢɢ ɩɥɚɧɟɬɵ ɩɨ ɷɥɥɢɩɬɢɱɟɫɤɨɣ ɬɪɚɟɤɬɨɪɢɢ, ɩɨɷɬɨɦɭ ɟɟ ɩɪɨɢɡɜɨɞɧɚɹ ɩɨ ɜɪɟɦɟɧɢ ɪɚɜɧɚ ɧɭɥɸ:
Ƚɥɚɜɚ 1. Ʉɢɧɟɦɚɬɢɤɚ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɢ ɩɪɨɫɬɟɣɲɢɯ ɫɢɫɬɟɦ |
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ɋɪɚɜɧɢɜɚɹ (1.112) ɫ ɜɵɪɚɠɟɧɢɟɦ (1.109) |
ɞɥɹ ɩɪɨɟɤɰɢɢ ɭɫɤɨ- |
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ɪɟɧɢɹ aM , |
ɜɢɞɢɦ, |
ɱɬɨ |
aM 0 . ɋɥɟɞɨɜɚɬɟɥɶɧɨ, |
ɭɫɤɨɪɟɧɢɟ ɜ ɥɸɛɨɣ |
ɦɨɦɟɧɬ ɜɪɟɦɟɧɢ ɢɦɟɟɬ ɬɨɥɶɤɨ ɩɪɨɟɤɰɢɸ ar , ɤɨɬɨɪɚɹ ɜ ɫɨɨɬɜɟɬɫɬ-
ɜɢɢ ɫ (1.109) ɹɜɥɹɟɬɫɹ ɮɭɧɤɰɢɟɣ ɩɪɨɢɡɜɨɞɧɵɯ ɩɨɥɹɪɧɵɯ ɤɨɨɪɞɢɧɚɬ ɩɨ ɜɪɟɦɟɧɢ.
ɉɪɨɞɢɮɮɟɪɟɧɰɢɪɭɟɦ ɨɛɟ ɱɚɫɬɢ ɭɪɚɜɧɟɧɢɹ ɬɪɚɟɤɬɨɪɢɢ (1.110)
ɩɨ ɜɪɟɦɟɧɢ: |
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ɂɫɩɨɥɶɡɭɹ ɭɪɚɜɧɟɧɢɟ ɬɪɚɟɤɬɨɪɢɢ (1.110) ɢ ɜɵɪɚɠɟɧɢɟ ɞɥɹ |
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ɫɟɤɬɨɪɧɨɣ ɫɤɨɪɨɫɬɢ (1.111), ɩɪɟɨɛɪɚɡɭɟɦ (1.113) ɤ ɜɢɞɭ: |
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rp 2Ve sinM |
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ɉɪɨɞɢɮɮɟɪɟɧɰɢɪɭɟɦ ɬɟɩɟɪɶ ɨɛɟ ɱɚɫɬɢ ɭɪɚɜɧɟɧɢɹ (1.114) ɩɨ |
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ɜɪɟɦɟɧɢ |
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r p 2Ve cosM M |
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Ɉɩɹɬɶ ɜɨɫɩɨɥɶɡɭɟɦɫɹ ɭɪɚɜɧɟɧɢɟɦ ɬɪɚɟɤɬɨɪɢɢ (1.110) ɢ ɜɵɪɚɠɟɧɢɟɦ ɞɥɹ ɫɟɤɬɨɪɧɨɣ ɫɤɨɪɨɫɬɢ (1.111) ɞɥɹ ɢɫɤɥɸɱɟɧɢɹ cosM ɢ M
ɢɡ (1.115): |
r p |
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rp 2Ve |
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ȼ ɪɟɡɭɥɶɬɚɬɟ ɧɚɯɨɞɢɦ:
r 4V 2 r p . (1.117) r3 p
Ⱦɥɹ ɧɚɯɨɠɞɟɧɢɹ ɢɫɤɨɦɨɣ ɩɪɨɟɤɰɢɢ ɭɫɤɨɪɟɧɢɹ ɩɥɚɧɟɬɵ ar , ɤɚɤ ɮɭɧɤɰɢɢ ɬɨɥɶɤɨ ɤɨɨɪɞɢɧɚɬ ɩɨɥɹɪɧɨɣ ɫɢɫɬɟɦɵ, ɩɨɞɫɬɚɜɢɦ r
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(ɫɦ. (1.111)) ɜ ɜɵɪɚɠɟɧɢɟ (1.109): |
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Ɍɚɤɢɦ ɨɛɪɚɡɨɦ, ɭɫɤɨɪɟɧɢɟ ɩɥɚɧɟɬɵ, ɞɜɢɠɭɳɟɣɫɹ ɩɨ ɷɥɥɢɩɬɢɱɟɫɤɨɣ ɬɪɚɟɤɬɨɪɢɢ, ɧɚɩɪɚɜɥɟɧɨ ɤ ɋɨɥɧɰɭ, ɧɟ ɡɚɜɢɫɢɬ ɨɬ ɩɨɥɹɪɧɨɝɨ ɭɝɥɚ M ɢ ɨɛɪɚɬɧɨ ɩɪɨɩɨɪɰɢɨɧɚɥɶɧɨ ɤɜɚɞɪɚɬɭ ɪɚɫɫɬɨɹɧɢɹ ɞɨ ɋɨɥɧ-
ɰɚ:
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ɆȿɏȺɇɂɄȺ. ɆȿɌɈȾɂɄȺ Ɋȿɒȿɇɂə ɁȺȾȺɑ |
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4V 2 |
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aM |
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Ɂɚɞɚɱɚ 1.12
(ɇɚ ɤɢɧɟɦɚɬɢɤɭ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ)
ɇɟɛɨɥɶɲɨɟ ɬɟɥɨ ɞɜɢɠɟɬɫɹ ɩɨ ɝɥɚɞɤɨɣ ɜɧɭɬɪɟɧɧɟɣ ɩɨɜɟɪɯɧɨɫɬɢ ɩɨɥɨɝɨ ɜɟɪɬɢɤɚɥɶɧɨɝɨ ɰɢɥɢɧɞɪɚ ɪɚɞɢɭɫɚ R. ȼ ɧɚɱɚɥɶɧɵɣ ɦɨɦɟɧɬ ɜɪɟɦɟɧɢ ɫɤɨɪɨɫɬɶ ɬɟɥɚ ɧɚɩɪɚɜɥɟɧɚ ɩɟɪɩɟɧɞɢɤɭɥɹɪɧɨ ɨɫɢ ɰɢɥɢɧɞɪɚ ɢ ɪɚɜɧɚ ȣ0 . Ɉɩɪɟɞɟɥɢɬɶ ɡɚɤɨɧɵ ɢɡɦɟɧɟɧɢɹ ɫɤɨɪɨɫɬɢ ɢ ɭɫɤɨ-
ɪɟɧɢɹ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɜ ɰɢɥɢɧɞɪɢɱɟɫɤɨɣ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ, ɚ ɬɚɤɠɟ ɭɝɨɥ D(t) ɦɟɠɞɭ ɫɤɨɪɨɫɬɶɸ ɢ ɭɫɤɨɪɟɧɢɟɦ.
Ɋɟɲɟɧɢɟ
I. Ȼɭɞɟɦ ɫɱɢɬɚɬɶ ɬɟɥɨ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɨɣ, ɤɨɬɨɪɚɹ ɞɜɢɠɟɬɫɹ ɩɨ ɰɢɥɢɧɞɪɢɱɟɫɤɨɣ ɩɨɜɟɪɯɧɨɫɬɢ ɫ ɩɨɫɬɨɹɧɧɨɣ ɜɟɪɬɢɤɚɥɶɧɨɣ ɫɨɫɬɚɜɥɹɸɳɟɣ ɭɫɤɨɪɟɧɢɹ, ɪɚɜɧɨɣ ɭɫɤɨɪɟɧɢɸ ɫɜɨɛɨɞɧɨɝɨ ɩɚɞɟɧɢɹ g .
Ⱦɥɹ ɪɟɲɟɧɢɹ ɡɚɞɚɱɢ ɜɵɛɟɪɟɦ ɰɢɥɢɧɞɪɢɱɟɫɤɭɸ ɫɢɫɬɟɦɭ ɤɨɨɪɞɢɧɚɬ, ɨɫɶ Z ɤɨɬɨɪɨɣ ɫɨɜɩɚɞɚɟɬ ɫ ɨɫɶɸ ɰɢɥɢɧɞɪɚ, ɤɚɤ ɩɨɤɚɡɚɧɨ ɧɚ ɪɢɫ. 1.18. ɇɚ ɬɨɦ ɠɟ ɪɢɫɭɧɤɟ ɢɡɨɛɪɚɠɟɧɵ ɨɪɬɵ er, eM ɢ ez ɰɢɥɢɧɞɪɢɱɟɫɤɨɣ ɫɢɫɬɟɦɵ. Ɉɫɶ, ɨɬ ɤɨɬɨɪɨɣ ɨɬɫɱɢɬɵɜɚɟɬɫɹ ɭɝɨɥ M ɫɢɫɬɟɦɵ
ɤɨɨɪɞɢɧɚɬ, ɧɚɩɪɚɜɢɦ ɧɚ ɩɨɥɨɠɟɧɢɟ ɬɟɥɚ ɜ ɧɚɱɚɥɶɧɵɣ ɦɨɦɟɧɬ ɜɪɟɦɟɧɢ.
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Ɋɢɫ. 1.18 |
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Ƚɥɚɜɚ 1. Ʉɢɧɟɦɚɬɢɤɚ ɦɚɬɟɪɢɚɥɶɧɨɣ ɬɨɱɤɢ ɢ ɩɪɨɫɬɟɣɲɢɯ ɫɢɫɬɟɦ |
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II. ȼ ɫɨɨɬɜɟɬɫɬɜɢɢ ɫ ɭɫɥɨɜɢɹɦɢ ɡɚɞɚɱɢ ɢ ɜɵɛɪɚɧɧɨɣ ɫɢɫɬɟɦɨɣ ɤɨɨɪɞɢɧɚɬ ɡɚɩɢɲɟɦ ɧɚɱɚɥɶɧɵɟ ɡɧɚɱɟɧɢɹ ɩɪɨɟɤɰɢɣ ɫɤɨɪɨɫɬɢ ɞɥɹ
ɪɚɫɫɦɚɬɪɢɜɚɟɦɨɝɨ ɬɟɥɚ: |
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ȼɨɫɩɨɥɶɡɭɟɦɫɹ ɮɨɪɦɭɥɚɦɢ (1.103) ɢ (1.104) ɞɥɹ ɩɪɨɟɤɰɢɣ ɫɤɨɪɨɫɬɢ ɢ ɭɫɤɨɪɟɧɢɹ ɬɟɥɚ ɧɚ ɧɚɩɪɚɜɥɟɧɢɹ, ɡɚɞɚɜɚɟɦɵɟ ɨɪɬɚɦɢ ɰɢ-
ɥɢɧɞɪɢɱɟɫɤɨɣ ɫɢɫɬɟɦɵ: |
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Ʉɪɨɦɟ ɬɨɝɨ, ɜ ɫɨɨɬɜɟɬɫɬɜɢɢ ɫ ɭɫɥɨɜɢɹɦɢ ɡɚɞɚɱɢ, ɡɚɩɢɲɟɦ: |
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III. ɂɫɩɨɥɶɡɭɹ (1.121) – (1.123), |
ɩɨɥɭɱɢɦ ɡɚɤɨɧɵ ɢɡɦɟɧɟɧɢɹ |
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ɩɪɨɟɤɰɢɣ ɫɤɨɪɨɫɬɢ ɢ ɭɫɤɨɪɟɧɢɹ: |
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Ɍɚɤɢɦ ɨɛɪɚɡɨɦ, ɢɫɤɨɦɵɣ ɡɚɤɨɧ ɢɡɦɟɧɟɧɢɹ ɫɤɨɪɨɫɬɢ ɢ ɭɫɤɨɪɟɧɢɹ ɜ ɰɢɥɢɧɞɪɢɱɟɫɤɨɣ ɫɢɫɬɟɦɟ ɤɨɨɪɞɢɧɚɬ ɢɦɟɟɬ ɫɥɟɞɭɸɳɢɣ ɜɢɞ:
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X0eM gtez , |
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Ɉɩɪɟɞɟɥɢɦ ɬɚɤɠɟ ɢɫɤɨɦɵɣ ɭɝɨɥ D ɦɟɠɞɭ ɫɤɨɪɨɫɬɶɸ ɢ ɭɫɤɨɪɟɧɢɟɦ ɬɟɥɚ:
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1.4. Ɂɚɞɚɱɢ ɞɥɹ ɫɚɦɨɫɬɨɹɬɟɥɶɧɨɝɨ ɪɟɲɟɧɢɹ
Ɂɚɞɚɱɚ 1
ɂɡ ɩɭɲɤɢ, ɧɚɯɨɞɹɳɟɣɫɹ ɧɚ ɫɚɦɨɥɟɬɟ, ɥɟɬɹɳɟɦ ɝɨɪɢɡɨɧɬɚɥɶɧɨ ɫɨ ɫɤɨɪɨɫɬɶɸ Xɫɚɦ , ɜɵɩɭɳɟɧ ɫɧɚɪɹɞ ɜ ɧɚɩɪɚɜɥɟɧɢɢ ɞɜɢɠɟɧɢɹ ɫɚɦɨ-
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ɆȿɏȺɇɂɄȺ. ɆȿɌɈȾɂɄȺ Ɋȿɒȿɇɂə ɁȺȾȺɑ |
ɥɟɬɚ. ɋɤɨɪɨɫɬɶ ɫɧɚɪɹɞɚ ɨɬɧɨɫɢɬɟɥɶɧɨ ɫɚɦɨɥɟɬɚ ɪɚɜɧɚ Xɫɧ . ɉɪɟɧɟɛ-
ɪɟɝɚɹ ɫɨɩɪɨɬɢɜɥɟɧɢɟɦ ɜɨɡɞɭɯɚ, ɧɚɣɬɢ:
1) ɭɪɚɜɧɟɧɢɟ ɬɪɚɟɤɬɨɪɢɢ ɫɧɚɪɹɞɚ ɨɬɧɨɫɢɬɟɥɶɧɨ Ɂɟɦɥɢ y( x) ;
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2) ɭɪɚɜɧɟɧɢɟ |
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ɨɬɧɨɫɢɬɟɥɶɧɨ |
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y ( x ) ; |
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3) ɭɪɚɜɧɟɧɢɟ |
ɬɪɚɟɤɬɨɪɢɢ |
ɫɚɦɨɥɟɬɚ |
ɨɬɧɨɫɢɬɟɥɶɧɨ |
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Ɉɬɜɟɬ: 1) |
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2 Xɫɚɦ Xɫɧ 2 |
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3) |
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0 . Ɉɫɢ X, X' ɢ X'' ɞɟɤɚɪɬɨɜɨɣ ɫɢɫɬɟɦɵ ɤɨɨɪ- |
ɞɢɧɚɬ ɧɚɩɪɚɜɥɟɧɵ ɝɨɪɢɡɨɧɬɚɥɶɧɨ ɜɞɨɥɶ ɫɤɨɪɨɫɬɢ ɫɚɦɨɥɟɬɚ, ɚ ɨɫɢ Y, Y' ɢ Y'' – ɜɟɪɬɢɤɚɥɶɧɨ ɜɜɟɪɯ, ɩɪɢ ɷɬɨɦ ɧɚɱɚɥɨ ɤɨɨɪɞɢɧɚɬ ɫɢɫɬɟɦɵ XY ɫɨɜɩɚɞɚɟɬ ɫ ɩɨɥɨɠɟɧɢɟɦ ɫɚɦɨɥɟɬɚ ɜ ɦɨɦɟɧɬ ɜɵɫɬɪɟɥɚ ɩɭɲɤɢ.
Ɂɚɞɚɱɚ 2
Ʌɨɞɤɚ ɩɟɪɟɫɟɤɚɟɬ ɪɟɤɭ ɲɢɪɢɧɨɣ d ɫ ɩɨɫɬɨɹɧɧɨɣ ɨɬɧɨɫɢɬɟɥɶɧɨ ɜɨɞɵ ɫɤɨɪɨɫɬɶɸ ȣ , ɩɟɪɩɟɧɞɢɤɭɥɹɪɧɨɣ ɫɤɨɪɨɫɬɢ ɬɟɱɟɧɢɹ ɪɟɤɢ, ɦɨɞɭɥɶ ɤɨɬɨɪɨɣ ɧɚɪɚɫɬɚɟɬ ɨɬ ɛɟɪɟɝɨɜ ɤ ɫɟɪɟɞɢɧɟ ɪɟɤɢ ɩɨ ɥɢɧɟɣɧɨɦɭ ɡɚɤɨɧɭ, ɦɟɧɹɹɫɶ ɨɬ 0 ɞɨ u. ɇɚɣɬɢ ɬɪɚɟɤɬɨɪɢɸ ɥɨɞɤɢ, ɚ ɬɚɤɠɟ ɫɧɨɫ ɥɨɞɤɢ l ɜɧɢɡ ɩɨ ɬɟɱɟɧɢɸ ɨɬ ɦɟɫɬɚ ɟɟ ɨɬɩɥɵɬɢɹ ɞɨ ɦɟɫɬɚ ɩɪɢɱɚɥɢɜɚɧɢɹ ɧɚ ɩɪɨɬɢɜɨɩɨɥɨɠɧɨɦ ɛɟɪɟɝɭ ɪɟɤɢ.
Ɉɬɜɟɬ: |
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x , ɩɪɢ y < d/2; |
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l 2X . Ɉɫɶ X ɞɟɤɚɪɬɨɜɨɣ ɫɢɫɬɟɦɵ ɤɨɨɪɞɢɧɚɬ XY ɧɚɩɪɚɜɥɟɧɚ ɜɞɨɥɶ
ɛɟɪɟɝɚ ɪɟɤɢ, ɚ ɨɫɶ Y – ɩɨɩɟɪɟɤ ɪɟɤɢ. ɇɚɱɚɥɨ ɫɢɫɬɟɦɵ ɤɨɨɪɞɢɧɚɬ, ɠɟɫɬɤɨ ɫɜɹɡɚɧɧɨɣ ɫ ɛɟɪɟɝɨɦ ɪɟɤɢ, ɫɨɜɩɚɞɚɟɬ ɫ ɦɟɫɬɨɦ ɨɬɩɥɵɬɢɹ ɥɨɞɤɢ.
Ɂɚɞɚɱɚ 3
ɉɨ ɞɜɢɠɭɳɟɦɭɫɹ ɜɧɢɡ ɷɫɤɚɥɚɬɨɪɭ ɫɩɭɫɤɚɟɬɫɹ ɩɚɫɫɚɠɢɪ ɫɨ ɫɤɨɪɨɫɬɶɸ X ɨɬɧɨɫɢɬɟɥɶɧɨ ɷɫɤɚɥɚɬɨɪɚ. ɋɤɨɪɨɫɬɶ ɷɫɤɚɥɚɬɨɪɚ ɪɚɜɧɚ u. ɋɩɭɫɤɚɹɫɶ ɩɨ ɧɟɩɨɞɜɢɠɧɨɦɭ ɷɫɤɚɥɚɬɨɪɭ ɩɚɫɫɚɠɢɪ ɩɪɨɯɨɞɢɬ N ɫɬɭɩɟɧɟɣ. ɋɤɨɥɶɤɨ ɫɬɭɩɟɧɟɣ N' ɩɪɨɣɞɟɬ ɩɚɫɫɚɠɢɪ, ɫɩɭɫɤɚɹɫɶ ɩɨ ɞɜɢɠɭɳɟɦɭɫɹ ɷɫɤɚɥɚɬɨɪɭ?