Chapter 19 Latest Board Questions Flashcards
A pump with capacity Q1 and head H1 is connected in series with another pump with capacity Q2 and head H2. What is the head developed if Q2 is less than Q1
B. H2 + H1
At ordinary temperature what substance will behave as inert gas and will not react in the combustion process
A. Nitrogen
Which of the following cycles is ideal for spark ignition in reciprocating engine
D. Otto cycle
What is the relative humidity when the dew point and dry bulb temperature are equal
C. 100 %
Reheating process is normally employed in steam plane when
C. Turbine undergoes excessive moisture
Where does the final removal of water vapor in an absorption refrigeration system occur
D. Rectifier
If the average temperature of liquid of power cycle during heat addition process is as high as possible, thermal efficiency of the cycle will
A. Increase
What is the temperature if lubricant at which it will ignite thus limit its application
C. Flash point
What is the heat that is removed from the space to be cooled, which is the same as the heat absorbed by the cooling coils
D. Refrigerating effects
An air conditioning system in which water is chilled or cooled and which passes the evaporator coils
A. Chilled water system
A multi stage refrigeration system which is realizable in using different refrigerants
B. Cascade
Very large pipe diameter means a thicker wall and high cost. It also means
B. High pressure drop
Aside from maintaining appropriate temperature for food cold storage, how is desiccation minimized or decreased
B. Maintain humidity ratio
During combustion process, only limited air is supplied and not enough to supply two molecule of oxygen per one molecule of carbon, then the product is
B. Carbon Monoxide
As far as combustion chamber design is considered the maximum power output of a given engine can be increased by
C. Decreasing combustion chamber volume
A water conservation device which employs both air and water is condensed a condenser and cooling tower combined into one is called
D. Evaporative condenser
In order to perform efficiently, a power cycle must be communicated with the outside temperature of its surroundings and into one is called
B. Second law of Thermodynamics
Water is heated in a container, it expands and becomes less dense and lighter. It rises up the container because of its reduced density and replaced by cooler air. As this process continues, the heat is transferred and disturbed all throughout. What is this mode of heat transfer called
D. Convection
When required, a regulator water valve in refrigerating system should be
D. In the water outlet
When there is no work between the thermodynamic system and its surrounding, the quantity of net heat transfer is equal to
D. Total energy of a closed system
In order to attain equilibrium in the condenser, the cooling tower range must be —– with respect to temperature rise in the condenser
B. Equal
If ice will form in a solution if water and salt, then it is at a temperature called
B. Freezing point depression
The flow of the convergent section if a nozzle is always subsonic. If the flow is subsonic then the mach number is
B. Less than unity
One hundred twenty percent theoretical air was supplied for combustion. What is the equivalent excess equal to
A. 20%
If Pi is the indicated horsepower and Pb is the indicated horsepower of a compressor, then what us mechanical efficiency, Em, equal to
B. Em = Pb/Pi
What is the least number of compressor a multistage system that will use
B. Two
The relation between the Fahrenheit absolute scale and the Celsius absolute scale is
A. R = 1.8 degree K
The sum of the internal energy and the product of pressure and specific volume is known as the.
A. Enthalpy
A refrigeration control that guards the compressor form overloads brought about by abruptly increases loads resulting from defrosting, warm products and others, is called
B. Suction hold back valve
What does fossil fuel fired power plants release, which in turn produces the key ingredient in acid rain
B. Sulfur emission
The fraction of the radiation energy incident on a surface which is absorbed by the surface is called
B. Absorptivity
Which of the following power plants uses energy from uranium to produce electric power
C. Nuclear plant
Ice cubes added to a glass of water and stirred. Moisture starts to form on the outer surface of the glass. At this point, what is the temperature at the outer surface called
C. Dew point temperature
The force when applied to a mass of one kilogram will give mass an acceleration of one meter per second for every second called
C. Newton
The kinetic energy of a moving fluid is used to isentropically compressed the fluid to state of zero velocity. The temperature of a moving fluid at the state zero velocity is called
A. Stagnation temperature
The dew point temperature of the products of combustion in the saturation temperature that corresponds to the partial pressure of the - — in the products
B. H2O
What do we call a device that is used to boiler operation that will stop the burner or at least send a signal to the operator if the water drops to a low level that is no longer safe
D. Low water cut off
Dry analysis is a fractional analysis of the products of combustion which does not include
A. Water vapor
The size of a reciprocating pump is stamped on the builder’s plate 3” x 4” x 6”. The diameter of the liquid cylinder is
D. 4”
One foot water is equal to
D. 62.43 lb/ft^2
The freezing point of R -22 is
C. -256 degree Fahrenheit
Which of the following is a type of evaporator
A. Shell and tube condenser