小霞用实验探究物体吸收热量跟物体的质量、升高的温度及物质种类的关系.他在三只相同

题型:问答题

问题:

小霞用实验探究物体吸收热量跟物体的质量、升高的温度及物质种类的关系.他在三只相同的烧杯中分别装入200g的水、400g的水和400g的煤油,用三个相同的酒精灯给它们加热.实验中小霞记录了如下数据.

加热时间/min0123456789
200g水的温度/℃20222426283032343638
400g水的温度/℃20212223242526272829
400g煤油的温度/℃20222426283032343638
通过分析表中的实验数据,回答下列问题:

(1)200g水升高4℃需加热2min,400g水升高4℃需加热4min.这说明:相同物质升高相同的温度,质量越大,吸收的热量越______.

(2)400g水升高4℃需要加热4min,400g煤油升高4℃需要加热2min.这说明:质量相同,升高温度相同,吸收的热量跟______有关.

考点:比热容的概念热量的计算
题型:问答题

下列叙述,哪项不正确()

A.右肺分为三叶

B.右肺门阴影比左肺门高

C.右膈高于左膈

D.气管分叉部相当第4~6胸椎高度

E.肺纹理由肺动脉、肺静脉构成

题型:问答题

女,35岁。左下颌下腺炎长期反复发作,双合诊左口底区可触及一硬结。为明确是否有结石,最正确的检查是()

A.拍牙片

B.B超检查

C.CT检查

D.MRI检查

E.拍下颌咬合片

题型:问答题

Mobile phones help us communicate everywhere, which is very important. They are good at emergencies, when you’ve (21) a car accident, for instance. A mobile phone (22) save your life! Mobile phones are also (23) because they have many good features--we can take photos and send them all over the world. But every coin has two sides. The (24) thing about mobile phones is that you have no privacy. My boss and friends find me whenever they want! I haven’t enjoyed a whole quiet day since the day I (25) my mobile phone. (26) disadvantage is that mobile phones make us lose good habits, such as punctuality. Before, when we (27) keep in touch so easily, if we had a date with someone, we tried our best to arrive (28) time. But now, because of the mobile phone, we are not afraid of (29) late any more, so, surprisingly enough, we make people wait! The third (30) I see is that I change my mobile phone once a year, and this means I’m spending (31) too much money on it. I think it is important to think (32) we use mobile phones. We should use things such as mobile phones, laptops, cameras, the Internet, and so on, (33) our needs. We can (34) our mobile phone when we don’t want to be disturbed by (35) . If we know how to use it, we can eliminate its disadvantages.

21()

A.have 

B.made 

C.had 

D.crashed

题型:问答题

在线电子支付的手段包括_______。

A.电子支票、智能信用卡、电子现金和电子钱包等等

B.电子转账、智能信用卡、电子现金和电子钱包等等

C.电子转账、VISA卡、电子现金和电子钱包等等

D.电子转账、VISA卡、电子现金和电子单证等等

题型:问答题

计算人工费、材料费、机械使用费。
2.分别计算直接工程费、措施费、规费、企业管理费。
3.计算直接费和间接费。
4.计算建筑安装工程费。

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