6. 1 300 10 / . . ? ?
, , . . !
t? ? . (4.6) (4.8) ? - ? , , (. 5). - ? , , , . ? (4.6) y (. 5):
0 = v t . (6.1)
, v0Y = v;
aY = g cos a, , y, p a. , 5 a, , ( ).
(6.1) ,
t = . (6.2)
l? , 1 (. 5) , . ? - ? , . ? , , . .
1 , ; , . , . . , 1 y .
? (4.8) y, . :
vY = 0; v0Y = v; aY = g cos a; SY = l; Þ
l = = . (6.3)
S? , x (. 5). (4.8) , (4.6) t (6.2). (4.6) (6.2), : SX = S; v0X = 0; aX = g sin a;
S = sin a = . (6.4)
a 0. , , .
, , , : t = 2,3 ; l = 5,9 ; S = 14 .
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- (4.6) (4.8) .
, .
7. 1*. a t . ?
a t t1 ? | . , . . | |
(4.6) (4.8)? , . , ? , . . . ? . ? | ||
, , . ? (4.6) (4.8) , . (), , , (), , .
? (4.6), (4.8). , . . .
(4.6) 1 x (. 6):
S1 = a t12 / 2. (7.1)
SX = S; v0X = 0; aX = a.
(4.7) t. x (. 6):
v1 = a t1. (7.2)
: t, S v1. , . ? ? t, (). t1 t? t t1. , (7.1) (7.2)? (. 6) 1, 1. ? (4.6) . x (. 6).
S1 = v1 (t t1) g (t t1)2 / 2. (7.3)
(7.1) (7.4). (7.1) (7.2) (7.3) :
(a + g) t12 2 t (a + g) t1 + g t2 = 0. (7.4)
(7.4) :
t1 = t . (7.5)
? (7.5) +, t1 > t, : . :
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t1 = t . (7.6)
( ) . . t , g .
: .
, : (4.6) (4.8) .
, ; .
, , . .
8. 1*. L H . , , L?
, . : AB BC (. 7). , .
, . , , . , . , , . , .
. , v1 = v2 = v a1 = a2 = a (. 7). , .
, 1 2 , 2 1 (.7). ?
, . , ? ABD. BD BC? , BC. ( ) .
, , , , . (4.6), t:
y (. 7) BD
v1 t cos a1+ g t2 / 2 = v t cos a + g t2 / 2;
BC
v2 t cos a2+ g t2 / 2 = v t cos a + g t2 / 2;
x (. 7) BD
v1 t sin a1 = v t sin a;
BC
v2 t sin a2 = v t sin a.
, BD BC.
? ( BC) ( BD). ABD ? , . , : v H, , 2 L.
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, (4.6) (. . 7) x y:
SX = v0 t > 2 L; (8.1)
SY = H = g t2 / 2. (8.2)
t,
t = Þ v0 > L (8.3)
. ( ) .