中国计量大学热工基础2014年、2017年、2018年考研真题试题

工程热力学部分（共75分）

一、选择题（每题2分，共20分）

1.有位发明家声称他设计了一种机器，当这台机器完成一个循环时，可以从单一热源吸收1000kJ的热，并输出1200kJ的功，这台热机（）。

A 既不违反第一定律，也不违反第二定律

B 违反了第一定律和第二定律

C 违反了第一定律

D违反了第二定律

2. 分别处于刚性绝热容器两侧的两种不同种类的理想气体，抽去隔板混合前后（）。（说明：S为熵，U为热力学能，H为焓）

A.ΔS=0、ΔU=0

B.ΔU=0、ΔH=0

C.ΔS=0、ΔH=0

D.ΔS>0、ΔU=0

3.质量不能改变的系统是（）。

A.开口系统

B.闭口系统

C.绝热系统

D.以上都是

4.闭口系统经历一可逆变化过程，系统与外界交换功量10KJ，换热-10KJ，则系统熵变（）。

A.大于0

B.小于0

C.等于0

D.不确定

5.在保温良好，门窗密闭的室内，启动一台打开门的冰箱，经过一段时间运行，则室温将（）。

A.升高

B.降低

C.不变

D.不确定

6.工质熵减少的过程（）。

A.不能进行

B.可以进行

C.必须伴随自发过程才能进行

《热工基础》试卷第1页共6页

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