1、 2018 2 26 1. 2. 3. , , , : , , 5. 6 7. 1 2 8. B C 9. S1 S2 L1 L2 , 10.2017 5 18 10 1kg 20 60 q =4.2 10 7 J/kg 3 21 11. A B C D 12. A B C D 13. A B C D 14 J/ 4.2 10 3 2.1 10 3 0.39 10 3 0.92 10 3 2.4 10 3 2.1 10 3 0.14 10 3 0.88 10 3A B C D 15. A B C D 16. A s1 S2 S3 B S2 C S1 D S2 S3 17 A B. C D 2
2、22 18. a b c d e 1 2 19. 1 A B 2 3 20 1 2 CD 21 4 +8 +9 21. c c t t 22. 90 150m 3 /h 1 50 2 90% 1.0 10 3 kg/m 3 c 4.2 10 3 J/ kg q=4 10 7 J/m 3 23. 108km/h 0.08 40 1375kg 25L q 7 J/kg 0.7 10 3 kg/m 3 g =10N/kg 1 2 3 : 2 26 1 2 3 4 5 6 7 8 ( ) 9 L1 L2 10 2.5 10 3 3 21 11 12 13 14 15 16 17 A C D B D B C 2 22 18 1 a d 2 b e 19 1 B 2 3 20 1 2 4 +8 +9 21 21 Q =Q 1 C M t =C M t 1 M =M c c 1 t t 1 22 1 m=1.5 10 5 Kg (1 ) Q =2.52 10 10 J (3 ) 2 Q =2.9 10 10 J 2 V=725m 3 2 23 1 m=17.5Kg (1 ) Q =5.775 10 8 J (3 ) 2 W =2.31 10 8 J (3 ) 3 F=f=1100N (2 ) S=2.1 10 5 m (2 )
