Questions And Answers Verified 100%
Correct
The efficiency of two centrifugal pumps operating in parallel is ___________ of one of
the pumps operating alone. - ANSWER practically the same as that
Assume that a spur gear having 20 teeth revolves at 80 r.p.m and drives another super
gear having 40 teeth. The speed at which the gear having 40 teeth revolves is
_____________ r.p.m. - ANSWER 40
A centrifugal pump has a plain flat-joint seal between the impeller and the casting. If the
clearance of the seal become enlarged due to wear, thereby reducing the pump's
efficiency, it would be GOOD practice to - ANSWER renew the impeller
The one of the following statement which CORRECTLY describes a speed
characteristic for a centrifugal pump under normal operating conditions is: - ANSWER
Total head varies directly with the square of the speed
The MAIN function of a pump stuffing box is to - ANSWER protect the pump against
leakage at the point where the shaft passes through the pump casting
The PROPER order of the event that takes place in a stroke internal combustion engine
- ANSWER Air intake, compression, power expansion, and exhaust
The number of cycles in an internal combustion engine is AT LEAST ____________
cycles. - ANSWER two
The lumens per watt taken by a lamp varies with the types and size of lamp. Given
that one candlepower light source emits 12.57 lumens, the lumens per watt taken by
a 75 candlepower lamp drawing 40 watts is APPROXIMATELY - ANSWER 23.6
A 230 volt, 25 cycle magnetic brake coil to be rewound to operate properly on 60 cycles
at the same voltage. Assuming that the coil 25 cycles has 1800 turns, at 60 cycles the
number of turns should be - ANSWER reduced to 750
Nichrome wire having a resistance of 200 ohms per 100 feet is to be used for a heater
requiring a total resistance of 10 ohms. The length, in feet, of wire required is -
ANSWER 50
,The MAIN reason for grounding conduit is to prevent the conduit from becoming -
ANSWER accidentally energized at a higher potential that ground
A feeder consisting of a positive and a negative wire supplies a motor load. The feeder
is connected to bus-bars having a constant potential of 230 volts. The feeder is 500 ft
long and consists of two 250,000 circular-mil conductors. The maximum load on the
feeder is 170 amps. Assume that the resistance of 1000 ft. of this cable is 0.0431 ohm.
The voltage, at the motor terminals, is MOST NEARLY
With the reference to Question 29, the efficiency of transmission, in percent, is MOST
NEARLY - ANSWER 217V; 97%
With reference to AC motors, in addition to overload, many other things causes fuses to
blow. The fuse will blow if, in starting an AC motor, the operator throws the starting
switch of the compensator to the running position - ANSWER too quickly
A change in speed of a DC motor of 10 to 15 percent USUALLY be made by -
ANSWER increasing or decreasing the gap between the armature and field
Of the following types of fire extinguishers, the one MOST suitable for use on fires in
electrical equipment is the ____________ extinguisher - ANSWER dry chemical
Portable fire extinguisher suitable for use on electrical fires are USUALLY identified by a
label with the following symbol __________ in a __________. - ANSWER C; circle
When flammable liquids are poured form one containers to another, a bond wire is
some-times connected between the containers to - ANSWER eliminate sparks due to
static electricity
The proper way to lift a heavy object includes all of the following techniques EXCEPT -
ANSWER Placing the feet as a far away from the object as possible
The contents of different piping systems are sometimes are sometimes identified by
means of standard color codes, such as the one recommended by the American
National Standards Institute (formerly the American Standard Institute). According to
this Institute's standards, a piping system used for fire protection should be designated
by the color - ANSWER red
Assume that the contents of a container are described as TOXIC. This means they are -
ANSWER poisonous
An authoritative source of emergency information on antidotes is the - ANSWER
Poison Control Center, Department of Health
, Unexpected operation of electrical equipment that can be started by remote control may
cause injury to workers making repairs. Before making repairs on such equipment, it is
GOOD practice to - ANSWER follow a lockout procedure
Assume that one of the men under your supervision asks you a technical question to
which you do not know the answer. Of the following, it is BEST that you - ANSWER tell
him that you do not know the answer but that you will get the information for him
In order standard cartridge fuses, it is necessary to specify only the - ANSWER current
capacity of the circuit and the power to be dissipated
A synchronous motor having 12 poles and operating on 60-cycles alternating current
would have a speed, in r.p.m., of MOSTLY NEARLY - ANSWER 600
In fully charged lead acid storage battery, the active material of the plates is -
ANSWER lead peroxide on the positive and sponge lead on the negative plates
Assume that a three-phase wound rotor induction motor is running at full speed and no
load when the connection between the windings and one of the collector rings suddenly
breaks. Under this condition, the motor will - ANSWER run at half speed
Of the following, the PRIMARY function of a pyrometer is to measure - ANSWER
temperature
In general, the temperature of a gas or vapor compressor in a limited space will -
ANSWER increase
Assume that the stem of a large valve has multiple threes. Of the following , the BEST
reason for using multiple threads in this instance is to - ANSWER permit the valve to
be opened or closed faster
Of the following, the valve generally used where accurate throttling is required such as
for instrument, gage, or meter line service is the ______________ valve. - ANSWER
needle
Of the following, the one which is NOT part of a safe, well-planned, lockout procedure is
- ANSWER furnish all plant personnel with identical padlocks and keys
Of the following, the BEST practical way to morale high among the men/women he
supervises is to - ANSWER praise the men/women when they do a good job
Of the following, the BEST procedure to use when it became necessary to reprimand a
worker is to - ANSWER reprimand him in a private rather than in pubic, even is you