如图所示,用弹簧测力计向上拉物块A,当弹簧测力计对物块A的拉力为F1(F1≠0)

题型:选择题

问题:

如图所示,用弹簧测力计向上拉物块A,当弹簧测力计对物块A的拉力为F1F1≠0)时,物块A对弹簧测力计的拉力为F2,物块A对水平地面的压力为N1N1≠0),水平地面对物块A的支持力为N2。已知物块A受到的重力为G,则下列分析中正确的是

A.拉力F1F2是一对平衡力

B.压力N1与重力G的大小相等

C.压力N1与支持力N2是一对相互作用力

D.拉力F1和支持力N2合力的大小与重力G的大小相等

考点:力的三要素
题型:选择题

腹水时()

A.腹部叩诊移动性浊音 

B.呕吐咖啡色液 

C.脑膜刺激征 

D.不能唤醒有浅反射 

E.昏迷病人呼吸有烂苹果味

题型:选择题

根据句意和首字母提示填空,完成下列句子。

1. Be c_____ of the dog that does not bark.

2. I haven't seen my cat for two days. I'm very w_____ about her.

3. Taiwan b_____ to China forever.

4. Three monkeys e_____ from the zoo. And it made us feel afraid.

5. He's always running for e_____ every morning.

6. She m_____ the bus and went late to school.

7. It's crucial that I study for it because it c_____ 30% to the final exam.

8. I'm really a_____, because I can't find my backpack.

9. Mark Twain is Mary's f_____ author.

10. You can't wake a person who is p_____ to be asleep.

题型:选择题

()等于某产品生产中生产要素的边际产量与边际收益的乘积。

A.边际收益

B.边际收益产量

C.边际产量

D.边际产值

题型:选择题

货物接运方式包括()。

A.库内接货

B.车站、码头提货

C.专用线接车

D.仓库自行接货

E.仓库自行送货

题型:选择题

对飞机进行横向操纵的是().

A.襟翼

B.缝翼

C.副翼

D.升降舵

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