1、 1 ( ) ( 40 ) A 1 ( ( ) A B C D AC A B C D 2 ( ) tan t (g 10 m/s 2 ) ( ) 92492172 A 1 s 5 m B 1 s 10 m C 5 m/s D 10 m/s AD tan gt v0 g v0 t g v0 1 v0 10 m/s D C 1 s 2 h 1 2 gt 2 1 2 2m 5 m A B 3 v0 h ( ) A v0 B v0 C h D v0 B t 2h g v0 A v gt 2gh v v 2 0 v 2 v 2 0 2gh B v tan 2gh v0 h C x v0t v0 2h g
2、 v0 D 4 A B O v0 x A P1 B P2 P1 P2 ( ) 92492173 A A B B A B x C A B D A B D O h h 1 2 gt 2 1 h sin 1 2 gsin t 2 2 t1 2h g t2 2h gsin 2 t1 t2 A x1 v0t1 x2 v0t2 x1 x2 B a1 g a2 gsin C A vA v 2 0 gt1 2 v 2 0 2gh B 3 vB v 2 0 a2 t2 2 v 2 0 2gh vA vB D 5 ) A B v1 v2 C B v1 v2 ( ) A B C D C A B C t 1 2 gt
3、 2 v1t v2 gt v1 v2 C 6 ) a b P a b P b a ( ) 92492174 A B C D D a b h 1 2 gt 2 a x v0t a A g v t g B v a ( ) a C D 7 ( ) A B C 3h 4 2h h M a b c ( ) A tA tB tC 3 2 B tA tB tC C L1 L2 ( 3 2 2 1) D L1 L2 AC A B C t 2h g 3 2 A B A B C 3 2 L1 L2 ( 3 2 2 1) C D 8 ) h 0.80 m L 0.50 m R 0.50 m v0 t h 1 2 g
4、t 2 t 2h g 0.4 s L v1t v1 1.25 m/s L 2R v2t v2 3.75 m/s 5 1.25 m/sv03.75 m/s. 1.25 m/sv03.75 m/s B 9 OAB R B C D OD OB C B ( ) 92492175 A R B R 2C. 3R 4D R 4D v0 D vy v0 gt v0 3. x R x v0t v 2 0 Rg 2 v 2 y 3Rg 2 . y v 2 y 2gy y 3R 4 BC y (R R R 4 D 10 ) O A B B AO A B O ( ) A. 2 B C 2 D 6 B P Q AP B
5、Q POA QOB B 11 ( ) a v1 b a v2 P ( ) 92492176 A v1 v2 B v1 v2 C b 2v2 D b 2v2 b a b AD P v2t v1tcos v1 v2 A B b 2v2 a b P b 2v2 C a b P b v1sin b 2v2 b P a b b a b D 12 ) M A B H 2.25 m C B C h 0.45 m M 0.25 0.6 0.8 g 10 m/s 2 . (1) M (2) B 7 (3) B A (1) M a mgsin cos ma a 8 m/s 2 . (2) C B B vBy v 2 By 2gh vBy 3 m/s B B vB vBy 5 m/s. (3) B A a t mgsin cos ma a 4 m/s 2 H h vBt 1 2 a t 2 t 0.5 s( 3 s ) (1)8 m/s 2(2)5 m/s (3)0.5 s
