如图所示,美国 “肯尼迪”号航空母舰上装有帮助飞机起飞的弹射系统.已知“F -

题型:计算题

问题:

如图所示,美国 “肯尼迪”号航空母舰上装有帮助飞机起飞的弹射系统.已知“F - A15”型战斗机在跑道上加速时可产生的最大加速度为5.0 m/s2,起飞速度为50 m/s.若要该飞机滑行100 m后起飞,则:

(1)弹射系统必须使飞机具有多大的初速度?(可保留根号)

(2)假设某航空母舰不装弹射系统,但要求该飞机能在它上面正常起飞,则该舰身长至少应为多少?

考点:匀变速直线运动的位移与速度的关系
题型:计算题

阅读下列一则材料,回答有关问题,

卫鞅曰:“治世不一道,便国不法古。故汤武不循古而王,夏殷不易礼而亡。反古者非,而循礼者不足多”。孝公曰日:“善。”以卫鞅为左庶长,卒定变法之令。——司马迁《史记·商鞅列传》

(1)商鞅变法的时间是那一年?当时在位的秦国国君是谁?

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(2)商鞅变法的法令中,有利于提高军队战斗力的是哪一条?

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(3)列出有利于“国富民强”的两项内容。

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(4)商鞅变法的历史影响是什么?

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(5)商鞅最后惨遭车裂而死,对此谈谈你的体会。

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题型:计算题

C

Very few people were coming to eat at the White Rose Restaurant and its owner did not know what to do . The food in its restaurant was cheap and good , but nobody seem to want to eat there .Then he did something that changed all that , and in a few weeks his restaurant was always full of men with their lady friends .Whenever a gentleman came in with a lady , a smiling waiter gave each of them a beautiful menu . The menu looked exactly the same on the outside , but there was an important difference inside . The menu that the waiter gave to the men gave the correct price for each dish and each bottle of wine , while the menu that he gave to the lady gave a much higher price . So when the man calmly ordered dish after dish and wine after wine , the lady thought he was much more generous than he really was .

54. How was the food in the White Rose Restaurant?___________ .

A. Its quality had always been good and its price low

B. It was poor and expensive at first and became much better and less expensive later

C. It was cheap and good at the beginning but became more expensive later

D. It looked beautiful on the outside but it was became more different inside

55. How did the restaurant attract so many people?______________ .

A. By lowering the price of its food

B. By improving the quality of its food

C. With waiters smiling at the guests when they came into the restaurant and giving them better service while they are

D. By showing men and women menus with different price on them

56. According to this passage , when a man and a woman ate at the restaurant the food was paid by whom ?_____________ .

A. Usually by the man and sometimes by the woman

B. Always by the man only

C. Sometimes by the man only and sometimes by both of the man and the woman

D. Normally by the woman

57. The White Rose succeeded because__________ .

A. women liked their men friends to be generous

B. men liked their women friends to be generous

C. men were more generous than women

D. women were more generous than men

题型:计算题

了解儿童的生长速度并了解其生长发育趋势,最直观的评价方法是均值离差法。()

题型:计算题

在资源管理器中,如果发生误操作将某文件删除,可以()。

A.在回收站中对此文件执行“还原”命令

B.从回收站将此文件拖回原位置

C.在资源管理器中执行“撤销”命令

D.以上均可

题型:计算题

简述英国高等教育的双重制。

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