MAE 201 NCSU Test 1 Questions with complete solutions

MAE 201 NCSU Test 1
Identify the system for a piston-cylinder.
a. closed system
b. open system
c. isolated system - Answer- a. closed system

Identify the system for a turbine.
a. closed system
b. open system
c. isolated system - Answer- b) Open system

Identify the system for a refrigerator and its immediate surroundings.
a. closed system
b. open system
c. isolated system - Answer- c. isolated system

Identify the system for a sealed tank.
a. closed system
b. open system
c. isolated system - Answer- a. closed system

In the first law, the energy entering the system and the energy leaving the system
can be due to

a. only work.
b. heat, work, and mass flow.
c. only work and mass flow.
d. only heat transfer. - Answer- b. heat, work, and mass flow.

The thermodynamic sign convention states that


Select one or more:
a. work transferred out of a system has a positive value.

b. the change of temperature in a system must be positive.

c. heat transferred out of a system can be positive or negative.

d. heat transferred into a system has positive value. - Answer- a. work transferred
out of a system has a positive value.

d. heat transferred into a system has positive value.

(T/F) Boundary work only exists if a system boundary is moved during a process. -
Answer- True