375 SET 2 Flashcards
(376 cards)
How do you call a measure of alkaline components in oils, especially those additives used in engine oils to neutralize acids formed during fuel combustion?
a) Neutralization number
b) Total base number
c) Total acid number
d) Neutralization number and total acid number
b) Total base number
Petroleum oils, when cooled, may become plastic solids, either from wax formation or from the fluid congealing. With some oils, the initial wax crystal formation becomes visible at temperatures slightly above the solidification point. When that temperature is reached at specific test conditions, it is known as the
a) Cloud point
b) Pour point
c) Creep point
d) Flash point
a) Cloud point
Which of the following types of alcohol is the most frequently considered as fuel for internal combustion engine?
a) Methyl alcohol
b) Isopropyl alcohol
c) Ethyl alcohol
d) Alcogas
c) Ethyl alcohol
The one that is an acceptor impurity element
A. Antimony
B. Gallium
C. Arsenic
D. Phosphorus
B. Gallium
It is a science of motion that can be solved in terms of scalar or vector algebra.
a) Kinematics
b) Curvilinear translation
c) Projectile
d) Acceleration
a) Kinematics
What is the basic index used to describe the radiant conditions in a space, it is the mean temperature of an individual; exposed surfaces in the environment?
a) Index temperature
b) Mean radiant temperature
c) Space temperature
d) Dry bulb temperature
b) Mean radiant temperature
Unless they are designed to flood, what is the important when removing condensate from heat exchangers?
a) Condensate is allowed to sub-cool before reaching the trap
b) Condensate is removed at steam temperature
c) Condensate should back-up into the steam pipe
d) That the trap is fatted level with or above the heater outlet
b) Condensate is removed at steam temperature
The hygroscopic moisture content of a substance expressed as a percentage of the bone-dry-weight of the material.
a) Moisture content
b) Regain
c) Bone-dry-weight
d) Gross weight
b) Regain
Which of the following is the most important consideration in a fire prevention program?
a) Train the staff to place flammable in fireproof containers
b) Know how to attack fires regardless of size
c) See that halls, corridors, and exits are not blocked
d) Detect and eliminate every possible fire hazard
d) Detect and eliminate every possible fire hazard
It is any one of a group of refrigerants that have been developed since about 1925 to overcome the irritating or toxic effects of refrigerants, such as ammonia and sulfur dioxide and the high condensing pressures required with carbon dioxide. How do you call these refrigerants?
a) Halogenated refrigerants
b) Freon refrigerants
c) Vacuum refrigerants
d) Halocarbon refrigerants
a) Halogenated refrigerants
The bottom blows down on a boiler is used to:
a) Remove mud drum water impurities
b) Increase boiler priming
c) Reduce steam pressure in the header
d) Increase the boiler water level
a) Remove mud drum water impurities
Which of the following gasket materials should be used on a Freon system?
A. Metallic
B. Asbestos
C. Rubber
D. A and B
D. A and B
It represents the rate, in Btu/hr or W, at which heat enters a conditioned space from an external source or is released to the space from an internal source during a given time interval.
a) Space heat gain
b) Space cooling load
c) Space heating load
d) Space heat extraction rate
a) Space heat gain
How do you call the ratio of the product of a convective heat transfer coefficient and the critical radius of the insulator to that of the thermal conductivity of the insulator?
a) Biot number
b) Prandtl number
c) Nusselt number
d) Reynolds number
a) Biot number
It is the temperature at which cooled oil will just flow under Specifc test conditions; and it indicates the lowest temperature at which a lubricant can readily flow from its container. How do you call this temperature?
a) Cloud point
b) Pour point
c) Creep point
d) Flash point
b) Pour point
For any particular tank temperature how does the heat loss from the lid of a closed tank compare with that of bottom?
a) They are approximately double those from the bottom
b) Losses from the top are approximately double those from the bottom
c) losses from the bottom are approximately double those from the top
d) losses from the top are approximately 4 times those from the bottom
b) Losses from the top are approximately double those from the bottom
Any refrigerant that exists as a liquid under normal atmospheric pressure and temperature must be vaporized in an evaporator under a pressure below atmospheric. This is sometimes referred to as:
a) Halogenated refrigerant
b) Freon refrigerant
c) Vacuum refrigerant
d) Halocarbon refrigerant
c) Vacuum refrigerant
Most of the bacteria in sewage are:
a) Saprophytic
b) Dangerous
c) Parasitic
d) Pathogenic
a) Saprophytic
Peaucellier mechanism has how many links?
a) 4
b) 5
c) 6
d) 8
d) 8
Which of the following is the rate at which the velocity is changing?
a) Acceleration
b) Linear
c) Motion
d) Vertical
a) Acceleration
Hard water is water, which contains soluble salts of which of the following elements?
A. Sodium
B. Sulfur
C. Calcium
D. Chlorine
C. Calcium
Why is slow, controlled warm-up of a steam system essential?
a) To make it easier to open the boiler main stop valve
b) To minimize undue stresses and eliminate damage
c) To permit separators to remove more water
d) To prevent stress on the boiler
b) To minimize undue stresses and eliminate damage
The relative humidity of saturated air is:
a. 0%
b. 75%
c. 25%
d. 100%
d. 100%
Ackerman steering gear is made up of
a) rolling and sliding pairs
b) rolling pairs
c) sliding and rotary pairs
d) turning pairs
d) turning pairs