问题
选择题
高速电力列车行驶时，受到的空气阻力，近似地与速度的平方成正比，列车行驶相同的路程时 [ ]
A. 车速越大，惯性越大，能耗越小
B. 车速越小，惯性越小，能耗越小
C. 车速越大，运行时间越短，能耗越小
D. 适当降低车速，可以大幅减小阻力，减少能耗
答案
答案：D
搜题请搜索小程序“爱下问搜题”
高速电力列车行驶时，受到的空气阻力，近似地与速度的平方成正比，列车行驶相同的路程时 [ ]
A. 车速越大，惯性越大，能耗越小
B. 车速越小，惯性越小，能耗越小
C. 车速越大，运行时间越短，能耗越小
D. 适当降低车速，可以大幅减小阻力，减少能耗
答案：D
— Now, tell me about the man who stole your neighbor’s car. What did he look like? — Well, sir. He was tall… — 小题1: Oh yes, and he was younger than you— only about thirty, I’d say. Well! And what colour was his hair? It was brown and short … it was similar to yours, actually. 小题2: No, he was clean-shaven OK. Now have a look at these photos —can you see him? 小题3: But that’s Frankie Farnbam — he’s got a beard, and he’s very short! Hm, well… 小题4: Yes, the strangest thing was that he appeared to be a gentleman —he was wearing a suit …Not like a thief at all. Hm, like this photo? Yes, that’s him ! That’s Bill Mahony: he’s in prison！ Are you sure you saw the thief？ 小题5:
|