斗堑瘁莆沏能箍蓝珊弘滩耻煎
对应课程:点击查看
起止时间:2021-04-12到2021-08-06
更新状态:每5天更新一次
Project 1 Basic concepts Quiz for Project 1
1、 Consider a submarine cruising 30 m below the free surface of seawater whose density is 1025 kg/m^3. The increase in the pressure exerted on the submarine when it dives to a depth of 110 m below the free surface is
A:480 kPa
B:804 kPa
C:1400 kPa
D:144 kPa
答案: 804 kPa
2、 The pressure drop in a duct is to be measured by a differential oil manometer. If the differential height between the two fluid columns is 3.2 cm and the density of oil is 860 kg/m^3, the pressure drop in the duct is
A:28 Pa
B:135 Pa
C:482 Pa
D:270 Pa
答案: 270 Pa
3、 The atmospheric pressures at the top and the bottom of a mountain are read by a barometer to be 93.8 and 100.5 kPa. If the average density of air is 1.25 kg/m^3, the height of the mountain is
A:5360 m
B:683 m
C:547 m
D:8200 m
答案: 547 m
Project 2 The first law of thermodynamics Quiz for Project 2
1、 A piston-cylinder device contains 3 kg of air at 300 kPa and 25 °C. During a quasi-equilibrium isothermal expansion process, 20 kJ of boundary work is done by the system, and 8 kJ of paddle-wheel work is done on the system. The heat transfer during this process is
A:28 kJ
B:20 kJ
C:36 kJ
D:12 kJ
答案: 12 kJ
2、 A bucket of water with a mass of 20 kg at 18 °C is to be cooled to 0 °C by dropping ice cubes at 0 °C into it. The latent heat of fusion of ice is 334 kJ/kg, and the specific heat of water is 4.18 kJ/kg.°C. The amount of ice that needs to be added is
A:4.5 kg
B:0.25 kg
C:10 kg
D:20 kg
答案: 4.5 kg
3、 An 8 L cylinder contains air at 300 kPa and 300 K. Now air is compressed isothermally to a volume of 2 L. The work done on air during this compression process is
A:119 kJ
B:1.8 kJ
C:3.3 kJ
D:4.5 kJ
答案: 3.3 kJ
4、 A 1.2 m^3 rigid tank contains nitrogen gas at 200 kPa and 350 K. Now heat is transferred to the nitrogen in the tank and the pressure of nitrogen rises to 900 kPa. The work done during this process is
A:840 kJ
B:0 kJ
C:156 kJ
D:240 kJ
答案: 0 kJ
Project 3 The second law of thermodynamics Quiz for Project 3
1、 A heat engine operates between the temperature limits of 1200 °C and 300 °C. If heat is supplied to the heat engine at a rate of 200 kJ/s, the maximum power output of this heat engine is
A:200 kW
B:327 kW
C:78 kW
D:122 kW
答案: 122 kW
2、 A heat engine receives heat from a source at 800 °C and rejects the waste heat to a sink at 40 °C. If heat is rejected from this engine at a rate of 80 kJ/s, the maximum power this heat engine can produce is
A:194 kW
B:1520 kW
C:80 kW
D:241 kW
答案: 194 kW
3、 A heat engine cycle is executed with steam in the saturation dome. The pressure of steam is 2 MPa during heat addition, and 0.1 MPa during heat rejection. The highest possible efficiency of this heat engine is
A:47%
B:53%
C:100%
D:23%
答案: 23%
Project 4 Properties of gases Quiz for Project 4
1、 A unit mass of an ideal gas at temperature T undergoes a reversible isothermal process from volume V1 to volume V2 while loosing heat to the surroundings at temperature T in the amount of q. If the gas constant of the gas is R, the entropy change of the gas Ds during this process is
如需购买完整答案，请点击下方红字：
获取更多中国大学mooc慕课答案，请点击这里，进入mooc.mengmianren.com
老厦棺董溃趴唐房曙孩吠擒帽