ͼ10
塢⣨2С⣬8֣ҪдҪ˵ʽֵ̡λʹ 284֣ij˳ƽֱ·ʻΪ˳ĿĵʱijѷƱ 1ʻʱ䣮 2ʻٶȣ
29.һƿӵ200gװˮʱ700g,װijҺʱ600g,ҺܶǶ?
TAXI ѷƱ E71238 130928 ϳ 1000 ³ 1005 2.00Ԫ 6.0km 16.00Ԫ ѧĩģ
һѡ⣨14С⣬ÿС2֣28֣
1 D 2 A 3 C 4 D 5 D 6 B 7 C 8 D 9 D 10 A 11 D 12 D 13 B 14 B ⣨ÿ1֣14֣
15. Bɣ 16. 17. 1.90 1mm 18. ֱ 19. 20. Զ ͼ⣨ 6֣
21.ͼ 22.ͼ 23.ͼ
ġ ʵ̽⣨ 14֣
24. ǰ¶Ȳߣʱ¶ȱֲ䣮ͼԣ 25. ĴСͬ
26. ڣϣ IJͬһ߶ȣ 27. 31.4 20 1.57103 塢 ⣨8֣ 28. ⣺ 1ʻʱΪt=10051000=5min=300s 2ʻ̣S=6.0km=6000m ٶȣ v===20m/s 𣺣1ʻʱΪ5min 2ʻٶΪ20m/s 29 V=500cm3 =0.8103kg/m3
꼶ѧĩģ
һѡ⣨15С⣬48֡1-12СΪѡ⣬ÿСֻһѡ⣬ÿС3֣13-15СΪѡ⣬ÿСѡ⣬ȫѡԵ4֣ѡԵȫ2֣ѡѡ÷֡ 1ߣճƺ AѧһֻЬijԼΪ24dm Bϴˮ60Ϊ CһѧԼ6000g Dеٶ1m/s
2һֻȾһЩй涨ѧУֹܱѣмķ֮ͬ A¼ڰװ豸 BѧУסլֲľ Cҹֹʩ DڸԱҪ϶ 3þƾƶձеıˮȣδۻʱˮ¶ Aˮ¶ Bˮ¶¶Ȳ C¶ Dˮ¶ȱ0治
4翵Ө¶ص˪ѩͬˮӣװʱաһʫʫȷ
A翵 BӨ¶Һ Cص˪ Dѩۻ
5죬˵ʱԿ죬ʱҲԿӱжΡԭȷ
AġDZҺ BġDZ CġǿҺ Dġǿ 6ڹĴ˵ȷ Aֱߴ Bֻڿֱߴ
CĴҪʣвܴ Dͬ־Ƚֱߴ 7йӦȷ Aʺ硪ķ C¥ֱߴ
BӰ롪ֱߴ DˮеӰ
8ڹ¼˵ȷ
AԹɢãֻܳ
Bʱʵڹϵõڹϵõ
CԶƽ澵ʱƽ澵ɵ֮С DҪ澵 9ͼУڹγɵ
AͨС׳ɵ Bƿھгɵ
CͼŴɵ Dͤˮгɵ
10ǵѧϰӦù㷺˵ȷ
AŴͼʱͼŴľӦһ Bۿ
CʱӦվھͷ DͶӰʹĻϳɵŴ
11ƽʱɲƫС Aںƽʱָƫֶ߾ֹͣĸ Bƽƽʱ˰˵̶ߴ Cʹĥ
Dʱͷƫұߣıֱ߲ 12йܶȵ˵ȷ
AһͰˮһСˮܶС Bܶȸȣɷ Cʵλkg/m3ȳõλg/cm3Ҫ Dܶʵԣ 13ͼʾijҺͼ
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