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The human internal body temperature is 98.6 degrees Fahrenheit. The body temperature in
degrees Centigrade is
A. 171.6 degrees C
B. 37.2 degrees C
C. 558.6 degrees C
D. 54.8 degrees C - correct answer ✔✔B. 37.2 degrees C
How many independent, intensive thermodynamic properties are required to completely
specify the state of a substance?
A. 1
B. 2
C. 3
D. 4 - correct answer ✔✔B. 2
If the mass of a substance is 12 kg and it occupies a volume of 3 m3, its specific volume is
A. 0.25 m3/kg
B. 4 m3/kg
C. 36 m3/kg
D. Not enough information to determine - correct answer ✔✔A. 0.25 m3/kg
If the absolute pressure inside a sealed container is 50 lbf/in2 and the local atmospheric
pressure is 14 lbf/in2, the gage pressure in the container is
A. 64lbf/in2
,B. 36 lbf/in2
C. 14.7 lbf/in2
D. Not enough information to determine - correct answer ✔✔B. 36 lbf/in2
For a fluid with constant density, how does the pressure in the fluid vary with depth?
A. the fluid pressure does not change with depth
B. the fluid pressure decreases linearly with depth
C. the fluid pressure increases linearly with depth
D. the fluid pressure increases with the square of the depth - correct answer ✔✔C. the fluid
pressure increases linearly with depth
For a defined system, heat and work transfer crossing the system boundary can be either
positive or negative.
True
False - correct answer ✔✔True
The units of heat and work are the same (e.g., kiloJoules)
True
False - correct answer ✔✔True
The work done during a process and the heat transfer during a process are path functions
True
False - correct answer ✔✔True
In a particular process 10 kJ of work is done on a system, 8 kJ of heat is transferred from the
system, 2 kJ is carried into the system with mass flow, and 5 kJ is carried out of the system with
mass flow. The change in energy of the system during this process is
, A. 15 kJ
B. 9 kJ
C. -1 kJ
D. 25 kJ - correct answer ✔✔C. -1 kJ
Efficiency is defined as the ratio of the desired output to the required input
True
False - correct answer ✔✔True
An electric motor draws 100 W of electrical power and produces 94 W of shaft power. What is
the efficiency of the motor?
A. 6.0%
B. 94.0%
C. 6.4%
D. Cannot be determined from the information - correct answer ✔✔B. 94.0%
Salad dressing--a mixture of vegetable oil, water, and vinegar--is a pure substance.
True
False - correct answer ✔✔False
Melting of solid materials occurs when energy is added permitting the intermolecular forces to
be overcome.
True
False - correct answer ✔✔True
A gas has higher specific volume than a liquid.
True