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Thermodynamics, Heat Transfer and Fluid Flow


Quiz Questions

1.The _______ of a body is the measure of the amount of material present in that body. The _______ of a body is the force exerted by that body when its mass is accelerated in a gravitational field.
Mass, weight
Weight, mass
2. Specific gravity (S.G.) is a measure of the relative density of a substance as compared to the density of water at a standard temperature.
True
False
3.______________________ is the mass of water vapor divided by a unit volume of air.
Relative humidity
Absolute humidity
4.Pressure is a measure of the force exerted per unit area on the boundaries of a substance. It is caused by the collisions of the molecules of the substance with the boundaries of the system.
True
False
5.Pressure is a measure of the molecular activity of a substance.
True
False
6.Potential energy and kinetic energy are ____________________ forms of energy.
Microscopic
Macroscopic
7.Entropy is sometimes referred to as a measure of the inability to do work for a given heat transferred.
True
False
8.An Isolated thermodynamic system is a system where neither mass nor energy can cross the boundaries and a ___________________ is a system where only energy can cross the boundaries
Closed thermodynamic system
Open thermodynamic system
9.The ________________________ is one in which the entropy of the fluid remains constant.
Isentropic process
Throttling process
10.Moisture (M) is defined as the ratio of the mass of the liquid to the total mass of both liquid and vapor.
True
False
11.The change of phase from solid to vapor is called __________________________.
Sublimation
Vaporization
12.The __________________ is a chart on which enthalpy (h) versus entropy (s) is plotted.
Mollier diagram
T-s diagram
13.The change in enthalpy of a fluid as it passes through a component can be determined using a Mollier diagram on steam tables.
True
False
14.The maximum efficiency of a closed cycle can be determined by calculating the efficiency of a Carnot cycle operating between the same value of high and low temperatures.
True
False
15.A fluid may be considered __________________ if one of the two conditions is true:

  • The fluid is a liquid.
  • The fluid is a gas with a velocity greater than one-third of the speed of sound in the gas.
Incompressible
Compressible