Page 72 - index

Ɇɵɫɚɥ. ɀԥɲɿɤɬɿԙ ABCD ԕɚԕɩɚԑɵ ɛɿɪɬɟɤɬɿ ɦɚɬɟɪɢɚɥɞɚɧ ɠɚɫɚɥԑɚɧ.
ɋɚɥɦɚԑɵ Ɋ 80ɧ ԕɚԕɩɚԕ ɚɲɵԕ ɬԝɪɭ ԛɲɿɧ DE ɬɿɪɟɝɿɦɟɧ ɬɿɪɟɥɿɩ ԕɨɣɵɥԑɚɧ

(69 ɚ-ɫɭɪɟɬ). Ȼɟɪɿɥɿɦɞɟɪ: AB b , AD AE a , ‘DAE D 300 .
Ɍɿɪɟɤɬɿԙ ɫɚɥɦɚԑɵɧ ɟɫɤɟɪɦɟɣ, ɨɫɵ ɬɿɪɟɤɬɿԙ ɿɲɤɿ ɤԛɲɿɧ ɠԥɧɟ A ɦɟɧ B

ɬɨɩɫɚɥɚɪɵɧɞɚԑɵ ɪɟɚɤɰɢɹɥɚɪɞɵ ɚɧɵԕɬɚɭ ɤɟɪɟɤ.
Ԕɚԕɩɚԕɬɵԙ ɬɟɩɟ-ɬɟԙɞɿɝɿɧ ԕɚɪɚɫɬɵɪɚɦɵɡ. Ɉɥ ԛɲɿɧ, A ɠԥɧɟ B ɬɨɩɫɚɥɚɪɵɧ

A2 , A3 , B2 , B3 ɪɟɚɤɰɢɹɥɚɪɵɦɟɧ, ɚɥ DE ɬɿɪɟɝɿɧ S ɪɟɚɤɰɢɹɫɵɦɟɧ

ɚɥɦɚɫɬɵɪɚɦɵɡ Ԕɚԕɩɚԕɬɵԙ ɫɚɥɦɚԑɵɧ ( Ɋ 80ɧ ) ɟɫɤɟɪɟ ɨɬɵɪɵɩ, 69 Ω-
ɫɭɪɟɬɿɧɞɟ ɤԧɪɫɟɬɿɥɝɟɧ ɟɫɟɩɬɟɭ ɧԝɫԕɚɫɵɧ ԕɚɛɵɥɞɚɣɦɵɡ. Ʉɨɨɪɞɢɧɚɬɚ ɛɚɫɵɧ A
ɧԛɤɬɟɫɿɧɟ ɛɟɤɿɬɿɩ, ɨɫɵ ɤԛɲɬɟɪ ɠԛɣɟɫɿ ԛɲɿɧ ɬɟɩɟ-ɬɟԙɞɿɤɬɿԙ ɚɥɬɵ ɬɟԙɞɟɭɥɟɪɿɧ
ԕԝɪɚɦɵɡ.

¦ ¦1. Fix 0 Ÿ 0 0 , 2. Fiy 0 Ÿ A2 B2 S ˜ cos E 0 ,

¦3. Fiz 0 Ÿ A3 B3 P S ˜sin E 0 , ¦4. M x (Fi ) 0 Ÿ

S ˜ AL P ˜ MN 0 ,

¦5. M y (Fi ) 0 Ÿ P ˜ AM B3 ˜ AB 0 , ¦6. M z (Fi ) 0 Ÿ

B2 ˜ AB 0 .

Ȼɟɪɿɥɿɦ ɛɨɣɵɧɲɚ Ⱥȿ AD ɛɨɥԑɚɧɞɵԕɬɚɧ E 900 D ɟɤɟɧɿɧ ɟɫɤɟɪɿɩ,
2

AL a ˜ cos D , MN a ˜ cos D , AM b
2 2 2

ԧɪɧɟɤɬɟɪɞɿ ɚɥɚɦɵɡ:

69-ɫɭɪɟɬ
Ⱥɥɵɧԑɚɧ ԧɪɧɟɤɬɟɪɞɿ ɩɚɣɞɚɥɚɧɵɩ, ɬɟɩɟ-ɬɟԙɞɿɤ ɬɟԙɞɿɤɬɟɪɿɧ ԕɚɣɬɚɞɚɧ
ɠɚɡɚɦɵɡ.

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