1、 - 1 - 01 1 (2017 ) v0=90km/h P=65KW a=7.5m/s 2 1 f 2 10s x 1 P=Fv 2 10s 2 10s 1 f 2600N 2 10s x 2 (2017 ) A B A mA=10.5kg B mB=1.5kg k=800N/m A F F t=0.2s t F - 2 - A F F A P 0.2s F F F F F F 3 (12 ) 20 s 15 m/s 240 s m 1000 kg P 90 kW P - 3 - 30 m/s. 1 J k 6 g (1) (2) (2) W f f P vm 3N W fx 1 2 mv
2、 2 m W fx 1 2 mv 2 m 7J kW 35.1 g (1)3750 m (2)35.1 g 4. 14 2017 13 r = 0.6m h = 3.2m R = 2.2m = 80% 1s m0 = 10kg g 10m/s 2 - 4 - 1 v 2 P 3 1h E 5 (12 ) (2017 ) m 1kg F t1 1s v t 1 f 2 1s F - 5 - 12 1 F a2 10m/s 2 1 f ma2 f 3 2 F a1 20m/s 2 1 F f ma1 F 3 1s 10m/s = m/s 2 20 + 0 = v 1 1s F W 300 = =
3、v F P 3 t W P / = 2 W P 1 6 23)(20 ) m l l 1.25 0.6 g (1) (2) - 6 - (2) v Wf mgl(1 Wf 1 2 mv 2 FT3 F3 F3 0.6F1 FT3 mg m v 2 l F3 FT3 Mg Wf 0.1mgl (1)3m (2)0.1mgl 7 20 2016 m=4kg =0.1 A 6m/s A F 0.5s 2.5m B t F A 3.75m g=10m/s 2 1 F t 2 A F WF - 7 - F A P t2 AP s F 2 A 1 t v t v a 1 1 2 A AP 2 0 a v
4、s 1 2 1.5s t AP 4.5m 3.75m s 1 F 3 t F 2 t t F f ( mg ) P M a2 2 - F f ma 1 2 PM 2 2 1 () 2 s a t t 1 M 2 2 () v a t t 1 M Q a3 3 f ma 1 2 M MQ 3 0 2 v s a 1 AQ AP PM MQ 3.75m s s s s 1 2 t s 1 2 1 WF=-F sAM 2 AM AP PM - s s s 2 WF= -51J 2 8 (12 ) m=2kg A 0 A B M P Q - 8 - F=5N A v0=8m/s A 10 3 t 2m
5、/s g=10m/s 2 1 t 2 F t 12 1 6 1 sin ma F mg f cos mg f (2 m F mg mg a sin cos 1 2 1 m/s 4 a s 5 . 1 4 8 2 1 0 2 1 a v v t (1 s 2 4 8 0 0 1 0 a v t s 2 - sin ma f F mg cos mg f (2 m mg F mg a cos sin 2 2 2 m/s 1 a s 2 1 0 2 0 2 2 a v t x s 4 2 x s t t t (1 1.5s 4s 2m/s - 9 - 9 (16 ) 2016 h=1.25m =70% H=5m S=2cm 2 R=10m = 3 kg/m 3 : 1 2 1s 3 - 10 - 10 (20 ) 2016 4 kw 4 kg 0.075 1 2 v0 466.7km/h 2 6 2 : 1 v km/h 2 1.5m/s 2 3 4 3 1 100m/s 1m 2 4 N 90% 2 1.3m 2 , - 11 - 3 45 1.29 10 1.3 2 8 0.9N 2.4 10 N m F 3 57 350000 2.4 10 W 2.3 10 W 3600 mm P F v 3
