(10分)如图所示,物体P从光滑的斜面上的A点由静止开始运动,与此同时小球Q在C

题型:计算题

问题:

(10分)如图所示,物体P从光滑的斜面上的A点由静止开始运动,与此同时小球QC点的正上方h处自由落下,P途经斜面底端B点后以不变的速率继续在光滑的水平面上运动,在C点恰好与自由下落的小球Q相遇,已知AB=BC=lh=4.5l,重力加速度为g,不计空气阻力,求:

(1)两球经多长时间相遇?(用g和l表示)

(2)斜面的倾角θ等于多大?

考点:自由落体运动
题型:计算题

If the rose can be said to be a special flower, then the apple can be said to be a special fruit. It is very important in American culture. American stories speak of Johnny Appleseed, who went throughout America collecting apple seeds and planting apple trees. He had a great love for nature and went through fields and farms adding richness and beauty to the country.

One of the first sayings taught to school children is, “An apple a day keeps the doctor away.” This short saying encourages children to eat fresh fruit to keep healthy. If someone always says good words to a person, people will call him an “apple polisher”. This, however, is not a good name. If someone is very dear to us, we say that he or she is the “apple of our eye”.

Most people believe that the fruit which Eve gave to Adam was an apple, even though the Bible(圣经) never says so. The apple, therefore, is a deep part of the language and stories of America.

An apple is also delicious. Apples can be cooked in many ways, used as a dessert, and made into sweet juice.

In many parts of the country during the harvest season, a popular activity is to go into an apple garden to pick apples. Washington, D. C. and New York are both famous for their apples.

Finally, when it’s time to take a vacation to American cities, one can always visit New York, which is “the biggest apple” of all the American cities.

小题1:What does the underlined phrase “apple polisher” mean?

A.Something for cutting apples.

B.A person who likes to please others.

C.A person who is dealing with fruits.

D.A machine for cleaning apples quickly.小题2:Which of the following is TRUE with apples?

A.Apples are medicine.

B.Apples are the most important food.

C.New York is famous for its big apples.

D.The Bible says Adam was given an apple.小题3:The passage is mainly about                             .

A.stories about the apple

B.apples in American culture

C.some famous sayings of the apple

D.big cities that is famous for apples

题型:计算题

尿比密降低的疾病,但除外()。

A.大量饮水

B.慢性肾盂肾炎

C.间质性肾炎

D.糖尿病

E.肾出血热多尿期

题型:计算题

成人气管的左右径为()。

A.2.0~2.5cm

B.1.0~1.5cm

C.0.5~1.5cm

D.2.0~3.0cm

E.2.5~3.0cm

题型:计算题

我们在日常生活中和影视作品中,常看到和听到信奉佛教的人双手合什,口念“阿弥陀佛”,这“阿弥陀佛”是指什么?()

A.一尊佛的名字

B.经典的经文警句

C.一种意念

题型:计算题

我国现行税法规定,个人的劳务报酬所得用于资助给高等学校研究新产品的研究开发经费,经主管税务机关确定,可以()。

A.全额在本次的劳务报酬所得中抵扣

B.全额在下次的劳务报酬所得中抵扣

C.可以在本次的劳务报酬所得中抵扣30%

D.可以在下次的劳务报酬所得中抵扣30%

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