运动员以一定的初速度将冰壶沿水平面推出,由于摩擦阻力的作用,其动能随位移变化图线

题型:不定项选择

问题:

运动员以一定的初速度将冰壶沿水平面推出,由于摩擦阻力的作用,其动能随位移变化图线如图所示,已知冰壶质量为19 kg,g取10 m/s2,则以下说法正确的是

[ ]

A.μ=0.05

B.μ=0.03                                                  

C.滑行时间t=5 s

D.滑行时间t=10 s

考点:动能定理匀变速直线运动的位移与时间的关系
题型:不定项选择

阅读短文,判断下列句子是否符合短文内容。符合的写“A”,不符合的写“B”。

Water is the most important in our lives. Not Many people understand this but it’s quite true. The human body can go without food for a long time. We’ve got many examples for this. Yet two or three dayswithout water can usually make people die. Man can’t live without water.

Many people don’t understand how much water the human body needs to work well, and many people, especially young people, do not drink enough water, even in very hot weather. About two thirds of our body is water. When we do sports, some of the water will get away from our body. If we don’t drink some water, our body won’t have enough water. And if we don’t have enough water, we’ll feel tired and many of us will get ill. So you know how important water is to us.

But at present we face water crisis(危机). Water is becoming less and less. So, we should protect water resources(资源) and try our best to save water in our daily life. Here are some tips for saving water:

1. Turn off the tap(水龙头) in lime.

2. Take shorter showers.

3. Don’t let water run while washing your face and reuse the water after we finish washing.

4. Encourage your friends and neighbors to join in the action of saving water.

小题1: Nobody can live without water.

小题2: About one third of our body is water

小题3: If one doesn't have enough water, he’ll feel tired and may get ill.

小题4: We’d better take longer showers and let water run while washing.

小题5: It’s our duty to protect water resources and save water.

题型:不定项选择

该图是某地附近两区域等值线分布图(比例尺相同)。读图回答问题。

小题1:右上图中A地海拔(H)范围和B地温度(T)范围是        (  )

A.1200米≤H<1500米 、6℃≤T<7.8℃

B.1000米≤H<1300米、.3℃≤T<4.8℃

C.1000米≤H<1300米、6℃≤T<7.8℃

D.1200米≤H<1500米、3℃≤T<4.8℃小题2:按照左图所示区域的大坝设计(坝顶的图上距离约为0.5厘米),则坝长和最大坝高(坝顶到坝底的垂直距离)大约分别是      (  )

A.坝长为50米 、最大坝高为145米

B.坝长为500米、最大坝高为150米

C.坝长为500米、最大坝高为145米

D.坝长为50米 、最大坝高为150米小题3:关于图中说法正确的是      (  )

A.ABCD四地的水都能汇入图中水域

B.EFG三地的海拔在750米以上800米以下

C.在E地观察不到车站N

D.铁路沿线要注意预防水库诱发的泥石流灾害

题型:不定项选择

休克时最能反映组织和细胞是否缺氧、缺氧程度、休克是否好转与恶化的主要实验室检查是 ( )

A.动脉血pH值
B.动脉血乳酸水平
C.血清钾离子浓度
D.血清乳酸脱氢酶含量
E.动脉血二氧化碳结合力

题型:不定项选择

制作木构件的榫接时,应该注意凿眼与开榫的配合,可采用锯不留线凿留线,合在一起整一线。( )

题型:不定项选择

采煤工作面遇到哪些情况必须制定安全措施?

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