1.单选题- (共3题)


A.可能为mg
B.可能为

C.可能为

D.可能为


A“天宫一号”的发射速度应介干第一宇宙速度与第二宇宙速度之间
B.对接前,“神舟八号”欲追上“天宫一号”,必须在同一轨道上点火加速
C.对接时,“神舟八号”与“天官一号”的加速度相等
D.对接后,“天宫一号”的速度小于第一宇宙速度

A.![]() |
B.![]() |
C.![]() |
D.![]() |
2.选择题- (共5题)
He tried hard to keep________in face of the policeman,but the sweat on his forehead gave him away.
Every year,because of the destruction of man,many of the earth's plants and animals are________.
阅读理解
“It is one of the few bright spots in the Chinese economy,” says Zeng Ming. He is talking about ecommerce. Mr. Zeng, the chief strategy officer of Alibaba, a giant Chinese Internet firm, predicts that digital transactions on his firm's platforms will top 1 trillion yuan ($ 159 billion) this year—more than Amazon's and eBay's combined. That is a bold claim; but consider what happened on Singles Sunday.
Invented a few years ago by students and seized upon by digital marketers, this festival for lonely hearts falls annually on the 11th day of the 11th month (since 1 is the loneliest number). It is like St Valentine's Day, only worse. Singletons shower each other with tender gifts: a barrage of pearls; a storm of sweets.
This November 11th they spent a surprising 19 billion yuan on Alibaba's online platforms—a fourfold increase from a year ago, and more than double what Americans spent online last Cyber Monday (the Monday after Thanksgiving, when retailers urge Americans to shop online). About 100 million purchases were logged, accounting for 80% of the packages shipped that day. Couriers(快递员) were buried in parcels.
So life is good for China's etailers, then? Not exactly. The number of digital marketers is increasing and online sales are booming. Consumers are enjoying lower prices, better service and more varieties. The problem? The pressure on profits in Chinese ecommerce is worse than that in America, reckons Elinor Leung of CLSA, a broker. “Almost no one makes money,” she says.
The fiercest battles are being fought between online retailers and their bricksandmortar (传统的实体企业) rivals. Dangdang, a firm that resembles Amazon, and 360buy, another online retailer, have cut prices fiercely. Tencent, a cashrich online giant known for its instant messaging software, is splashing out to win market share. 360buy has also just raised $ 400 million from investors to do the same. But it is unclear how much longer such firms can burn through capital.
阅读理解
“It is one of the few bright spots in the Chinese economy,” says Zeng Ming. He is talking about ecommerce. Mr. Zeng, the chief strategy officer of Alibaba, a giant Chinese Internet firm, predicts that digital transactions on his firm's platforms will top 1 trillion yuan ($ 159 billion) this year—more than Amazon's and eBay's combined. That is a bold claim; but consider what happened on Singles Sunday.
Invented a few years ago by students and seized upon by digital marketers, this festival for lonely hearts falls annually on the 11th day of the 11th month (since 1 is the loneliest number). It is like St Valentine's Day, only worse. Singletons shower each other with tender gifts: a barrage of pearls; a storm of sweets.
This November 11th they spent a surprising 19 billion yuan on Alibaba's online platforms—a fourfold increase from a year ago, and more than double what Americans spent online last Cyber Monday (the Monday after Thanksgiving, when retailers urge Americans to shop online). About 100 million purchases were logged, accounting for 80% of the packages shipped that day. Couriers(快递员) were buried in parcels.
So life is good for China's etailers, then? Not exactly. The number of digital marketers is increasing and online sales are booming. Consumers are enjoying lower prices, better service and more varieties. The problem? The pressure on profits in Chinese ecommerce is worse than that in America, reckons Elinor Leung of CLSA, a broker. “Almost no one makes money,” she says.
The fiercest battles are being fought between online retailers and their bricksandmortar (传统的实体企业) rivals. Dangdang, a firm that resembles Amazon, and 360buy, another online retailer, have cut prices fiercely. Tencent, a cashrich online giant known for its instant messaging software, is splashing out to win market share. 360buy has also just raised $ 400 million from investors to do the same. But it is unclear how much longer such firms can burn through capital.
阅读理解
“It is one of the few bright spots in the Chinese economy,” says Zeng Ming. He is talking about ecommerce. Mr. Zeng, the chief strategy officer of Alibaba, a giant Chinese Internet firm, predicts that digital transactions on his firm's platforms will top 1 trillion yuan ($ 159 billion) this year—more than Amazon's and eBay's combined. That is a bold claim; but consider what happened on Singles Sunday.
Invented a few years ago by students and seized upon by digital marketers, this festival for lonely hearts falls annually on the 11th day of the 11th month (since 1 is the loneliest number). It is like St Valentine's Day, only worse. Singletons shower each other with tender gifts: a barrage of pearls; a storm of sweets.
This November 11th they spent a surprising 19 billion yuan on Alibaba's online platforms—a fourfold increase from a year ago, and more than double what Americans spent online last Cyber Monday (the Monday after Thanksgiving, when retailers urge Americans to shop online). About 100 million purchases were logged, accounting for 80% of the packages shipped that day. Couriers(快递员) were buried in parcels.
So life is good for China's etailers, then? Not exactly. The number of digital marketers is increasing and online sales are booming. Consumers are enjoying lower prices, better service and more varieties. The problem? The pressure on profits in Chinese ecommerce is worse than that in America, reckons Elinor Leung of CLSA, a broker. “Almost no one makes money,” she says.
The fiercest battles are being fought between online retailers and their bricksandmortar (传统的实体企业) rivals. Dangdang, a firm that resembles Amazon, and 360buy, another online retailer, have cut prices fiercely. Tencent, a cashrich online giant known for its instant messaging software, is splashing out to win market share. 360buy has also just raised $ 400 million from investors to do the same. But it is unclear how much longer such firms can burn through capital.
3.解答题- (共3题)

(l)滑块冲上小车后小车的加速度;
(2)判断滑块能否滑离小车;若能滑离,求滑块落地时距车右端的水平距离,若不能滑离,求滑块相对车静止时离车右端的距离。


(1)小车在CD轨道上运动的最短路程;
(2)赛车电动机工作的时间。

(l)试求B球质量m;
(2)从碰后到刚好分离过程中A对B的库仑力所做的功。
4.实验题- (共1题)

(l)若轨道完全光滑,则x2与h的理论关系应当满足x2=____。(用H、h表示)
(2)该同学经实验得到几组数据如表所示,请在图乙所示的坐标纸上作出x2一h关系图________。

对比实验结果与理论计算得到的x2一h关系图线(图乙中已画出),可知自同一高度由静止释放的钢球,其水平抛出的速率____(填“小于”或“大于”)理论值。
(3)实际上轨道是不光滑的,钢球下滑过程需要克服摩擦力做功,已知测得钢球的质量为m,则钢球在下滑过程中克服摩擦力做功大小为________
-
【1】题量占比
单选题:(3道)
选择题:(5道)
解答题:(3道)
实验题:(1道)
-
【2】:难度分析
1星难题:0
2星难题:0
3星难题:0
4星难题:3
5星难题:0
6星难题:3
7星难题:0
8星难题:1
9星难题:0