1、 1 3 1 1 (1) (2) (3) 2 (v) v s t r T m/s ( ) t T rad/s (T) (n) (f) T r v s n r/s r/min f Hz (a) a v 2 r 2 m/s 2 2 1 2 F m v 2 r 2 r m 2 T 2 r 2 mf 2 r. 2 3 4 3 1 2 3 (1) Fn 2 r (2) Fn 0 (3) Fn 2 r (4) Fn 2 r 1 (1) (2) (3) (4) (5) (6) 2 ( ) A B C D C F 2 r. F 0 3 F gr N mg m v 2 r N v 7 1 1 ) A B A B
2、 ( ) A A B B A C B D B C F 2 A A OO B OO B B C B B D 2 ( ) m A A A A A OO L. OO . A ( ) 92492179 A B C L D L AC . f OO f 8 2 f L f f OO f 2 2 L A OO B D A C 2 3 R r ( ) A vmin g R r B vmin gR C ab D ab C A B ab C ab D 1 2 3 ) Q Q O x L 6 m v0 4 m/s. m 1 kg xP 2 m P Q 9 N 0.4 g 10 m/s 2 . (1) N yN (2
3、) (1) a 4 m/s 2 x1 v 2 0 2a 2 m (L xP) 4 m v0 Q N mg m v 2 N R Q N 1 2 mv 2 0 1 2 mv 2 N 2mgR R 0.32 m yN 2R 0.64 m. (2) N x L x1 x R M x2 gx2 mgR x2 0.8 m x 6 m x x 6 m (1)0.64 m x x 6 m 1 1 ) ABC O P A OA 1 PA 2. ( ) 92492180 10 A tan 1tan 2 2 B tan 2 tan 1 2 C tan 1tan 2 1 2D tan 2 tan 1 1 2A A 1 tan 1 vy v0 gt v0 2 tan 2 x y v0t 1 2 gt 2 2v0 gt tan 1tan 2 2. A B C D 2 2 A l ( ) A B C D O D mgl 1 2 mv 2 A T mg m v 2 l T 3mg A B O H H l 1 2 gt 2 x vt x 2 H l l O C D 11