电阻R1、R2、R3串联在电路中,已知R1两端的电压为6V,R2两端的电压为12

题型:多选题

问题:

电阻R1、R2、R3串联在电路中,已知R1两端的电压为6V,R2两端的电压为12V,下列说法错误的是 [ ]

A.电路中的电流为0.6A

B.电阻R2的阻值为20

C.三只电阻两端的总电压为21V

D.电阻R3消耗的电功率为3.6W

考点:欧姆定律
题型:多选题

工业上合成氨的反应是:N2(g)+3H2(g)2NH3(g)   ΔH=-92.20 kJ·mol-1

(1)下列事实中,不能说明上述可逆反应已达到平衡的是________        

①单位时间内生成2n mol NH3的同时生成3n mol H2

②单位时间内生成n mol N—H的同时生成n mol N≡N

③用N2、H2、NH3的物质的量浓度变化表示的反应速率之比为1︰3︰2

④N2、H2、NH3的体积分数不再改变

⑤混合气体的平均摩尔质量不再改变

⑥混合气体的总物质的量不再改变

(2)已知合成氨反应在某温度下2L的密闭容器中进行,测得如下数据:

时间(h)

物质的量(mol)

01234
N21.50n11.20n31.00
H24.504.203.60n43.00
NH300.20N21.001.00
根据表中数据计算:

①反应进行到2小时时放出的热量为________          

②0~1小时内N2的平均反应速率________  mol·L-1·h-1

③此条件下该反应的化学平衡常数K="  " ________     (保留两位小数)

④反应达到平衡后,若往平衡体系中再加入N2、H2和NH3各1.00mol,化学平衡将向________ 方向移动(填“正反应”或“逆反应”、“不移动”)。

题型:多选题

 手掌按住正在发声的鼓面,鼓声消失了.这个实验能探究的是(  )

A.决定音调的因素

B.声音能否在空气中传播

C.声音产生的原因

D.声音传播是否需要时间

题型:多选题

病人症见发热恶风,汗出,胸胁胀痛,嘿嘿不欲饮食,口苦欲呕,眩晕,舌苔白,脉浮缓。其证候是

A.太阳阳明合病

B.太阳少阳合病

C.少阳阳明合病

D.太阳少阴合病

E.太阳厥阴合病

题型:多选题

阅读理解。

     Going on a date can be a nightmare for the best of us. But now a pair of 'social X-Ray' glasses

promises to tell you exactly what the other person is thinking-and when you should stop talking.

     The glasses have a built-in camera which monitors the other person's facial expressions and matches

them up with 24 known features which convey emotions. It will then tell the individual via an earpiece and

lights on the glasses what their date is thinking. In a traffic light-style system, a red light means negative,

yellow means they are a bit interested and green means your date is happy. The glasses are under

development at present by researchers at the Massachusetts Institute of Technology's Media Lab.

     They say that wearing them during a conversation with another person is like having an 'extra sense'

that they are bored or losing interest.

     The eyewear was developed for people suffering from autism (孤独症) who have much difficulty

interacting with others, but now the team behind it has seen wider applications. It works thanks to a

camera the size of a grain of rice which is put into the glasses frame and connected via a wire to a small

computer which can be attached to the user's body. The camera monitors how long and how often 24

'feature points' appear on the subject's faces which are then analyzed by software developed by the MIT

team.

     This data is then compared with a bank of expressions and the computer tells the wearer what is

going on via the earpiece and the traffic light system.

     So far the glasses are still a job in progress and have been accurate just 64 per cent of the time, a

figure which is expected to improve with further tests.

1. The passage mainly tells us that _______.

A. going on a date can be a nightmare for the best of us

B. scientists are showing more and more concern to people suffering from autism

C. the glasses will be more and more popular

D. the scientists are working on a new type of glasses to help people going on a date

2. Which of the following is true according to the passage? 

A. The glasses were initially intended for helping people going on a date.

B. The glasses are widely used and have achieved great success.

C. The built-in camera in the glasses is of great importance.

D. People wearing the glasses are sure to have a good date.

3. The underlined word ''interacting'' in Paragraph 4 can be replaced by _______ . 

A. communicating

B. reacting

C. affecting

D. acting

4. Which is right according to Paragraph 2 ?  

A. Red = negativeyellow = neutral        green = positive

B. Red = positiveyellow = neutral        green = negative

C. Red = neutralyellow = positive       green = negative

D. Red = negativeyellow = positive       green = neutral

5. The passage is probably from _______ . 

A. a guide book      

B. an autobiography book         

C. a leaflet          

D. a scientific report

题型:多选题

提出"刺有大小"的文献是()

A.《内经》

B.《难经》

C.《针灸甲乙经》

D.《针经指南》

E.《针灸大成》

更多题库