1、 2016-2017 2 20 1 A B C D 2 A B C D 3 150W A 150J B 150J C 150J D 150W 4 1 A B C D 5 G F 5N A 5N B 5N C 5N D 6 AOB B G A A F 2 B F 4 C F 1 D F 3 7 A A B B C A D B 8 A J/S B W/S C W D N m/s 9 10m A 500W B 500J C 5000W D 5000J 10 O A F G F A B C D 2 24 11 “ ” “ ” 100N 5 F N 12 1000N N N 13 A 500N N 1m
2、in 20 0.3m 1min J W 14 l/m G/N W/J t/s P/W 0.6 500 5 12 15 1 2 2+2+6+6+10 26 16 OA F 1 F 2 A F 1 OO 1 F 2 F 2 F 1 L 1 17 18 “ ” A B m A m B 1 2 3 19 1 “ ” “ ” 2 F 1 /N L 1 /m F 2 /N L 2 /m 1 1.0 0.24 2.0 0.12 2 1.5 0.1 0.5 3 4 0.5N N / / 20 2N 1 G N F N h m s m W J W J 2 2 G N F N h m s m W J W J 4
3、1.5 0.1 0.3 0.4 0.54 88.9% 6 2.2 0.1 0.3 0.6 0.66 90.9% 3 “ ” “ ” 6+6+8 20 21 “ ” 8s 120m 3000N 1 2 3 22 220N 20N 5s 6m 1 2 3 23 810 4 N 0.03 80% 1 2 0.1m/s 2016-2017 2 20 1 A B C D A A B B C C D D B 2 A B C D A B C D B 3 150W A 150J B 150J C 150J D 150W 1 2 1W=1J/s 1s 1J 150W=150J/s 1s 150J A B D C
4、 C 4 1 A B C D 4 5=20 210=20 3 5=15 1 10=10 B 5 G F 5N A 5N B 5N C 5N D L OA L OB L OA L OC =L OB FL OA =GL OB L OA L OB G F=5N B 6 AOB B G A A F 2 B F 4 C F 1 D F 3 F 1 L 1 =F 2 L 2 F 3 OA F 3 OA F 1 L 1 =F 2 L 2 F 3 F 3 D 7 A A B B C A D B A C 8 A J/S B W/S C W D N m/s W kW J/s N m/s A J/s W J/s W
5、 A B W S W/S B C W C D N m N m/s P= D B 9 10m A 500W B 500J C 5000W D 5000J 50kg G=mg=50kg 10N/kg=500N W=FS=Gh=500N 10m=5000J D 10 O A F G F A B C D = L G = O B cos L F = O A co s GL G =FL F F= G OB OA F C 2 24 11 “ ” “ ” 100N 5 F 20 N F F L =F L F =20N 20 12 1000N 1000 N 500 N 1000N 500N 1000 500 13 A 500N 300 N 1min 20 0.3m 1min 1800 J 30 W 1 2 W=FS P= 1 2 F 1 L 1 =F 2 L 2 F 1 1.5m=500N 0.9m F =F 1 =300N 1min W=nFs=20 300N 0.3m=1800J P=30W 300 1800 30 14