решения курсовых (семестровых) работ из задачника / Статика / C05_16
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,
, .
( ) .
: G = 1.2 H , Q = 15 H , a = 0.20 , b = 0.45 , = 0.04 , α = 45 , f = 0.25 .
: P, RO , RA.
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. 1
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! , Q
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( . 1). ! Q, N1. |
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Q ! , |
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: Yi = 0; T − Q = 0 |
T = Q = 15 . |
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" , ( .1): |
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MO (Fi ) = 0; |
T′ × 2R + T′ × R - F × 3R = 0, |
(1) |
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#F - ( );
T′ − , ! (T′ = = Q = 15 ).
Xi = 0; |
O - T¢cos 45 - N2 cos 45 + F sin 45 = 0; |
(2) |
Yi = 0; |
YO + T¢sin 45 - T¢ - G - N2 sin 45 - F cos 45 = 0; |
(3) |
$ # ,
( )
F = f N2. |
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(4) |
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% (1) – (4) : F = ′ = 15 ; |
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N2 = |
F |
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15 |
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= 60 ; |
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f |
0.25 |
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O = T¢cos 45 + N2 cos 45 - F sin 45 = (15 + 60 -15) × 0.5 |
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= 30 |
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» 42.426 ; |
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YO = -T¢sin 45 + T¢ + G + N2 sin 45 + F cos45 = -15×0.5 |
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+15 +1.2 + 60×0.5 |
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+15×0.5 |
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2 |
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YO = 16.2 + 30
2 » 58.626 ;
RO = 
XO2 + YO2 = 
42.4262 + 58.6262 » 72.368 .
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#
, ## ( . 1):
M (Fi ) = 0; |
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N2a - F - Psinα × (a + b) = 0, |
(5) |
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Xi = 0; |
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A - P cosα + F = 0; |
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(6) |
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Yi = 0; |
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YA + sinα - N2 = 0; |
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(7) |
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(5) – (7), : |
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N2a − F |
60 × 0.20 -15 × 0.04 |
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11.4 |
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P = |
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» 24.803 ; |
sinα (a + b) |
sin 45 × (0.20 + 0.45) |
0.5 |
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× 0.65 |
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A = P cosα - F = 24.803× cos 45 -15 » 2.538 ; YA = N2 - sinα = 60 - 24.803 × sin 45 » 42.462 ;
R = 
X 2 + Y 2 = 
2.5382 + 42.4622 » 42.538 .
: P = 24.803 ; RO = 72.368 ; R = 42.538 .