fml2 Flashcards
Transformers designed for higher frequencies require much less iron core and windings than those designed for low frequencies. How is this frequency created? (Multiple Choice)
Question options:
A) By using the inverter principle to create high frequency AC
B) By adding a high frequency stabilizing circuit to the output circuit
C) By placing the rectifier on the output side of the transformer
D) By placing metal oxide varistors in parallel with the inlet rectifier
A) By using the inverter principle to create high frequency AC
The term laser is an acronym for : (Multiple Choice)
Question options:
A) light accelerated by selenium emitting radiation.
B) light amplification by stimulated emission of radiation.
C) light aligned to stimulate emission of radiation.
D) light amplification by stimulated electron radiation.
B) light amplification by stimulated emission of radiation.
With the GMAW process and a CV power source, the welding current is determined by: (Multiple Choice)
Question options:
A) the slope of the static characteristic.
B) the setting on the welding power source.
C) the open circuit voltage.
D) the wire feed speed.
D) the wire feed speed.
What is the effect of frequency modulation when transistors are used for a DC power supply? (Multiple Choice)
Question options:
A) Changes in wire feed speed cause an increase in heat input
B) Widening of the arc
C) Increased droplet size
D) Increase puddle fluidity
A) Changes in wire feed speed cause an increase in heat input
Two examples of good semi-conductors are: (Multiple Choice)
Question options:
A) copper and silicon.
B) silicon and germanium.
C) selenium and aluminum.
D) germanium and steel.
B) silicon and germanium.
If the total length of a cable is 18 metres, which cable according to AWG (American Wire Gauge) would give you better conductivity? (Multiple Choice)
Question options:
A) 4
B) 2
C) 1
D) 1/0
C) 1
What binder is used for the fabrication of coating welding electrodes? (Multiple Choice)
Question options:
A) Potassium
B) Sodium or potassium silicate
C) Iron oxide
D) Rutile
B) Sodium or potassium silicate
Why is the concept of concentricity in the manufacturing of covered electrodes important? (Multiple Choice)
Question options:
A) Because it helps in the handling of the electrode
B) For cosmetic reasons
C) To facilitate the arc starting
D) None of the above
A) Because it helps in the handling of the electrode
The AWS classification BAg-XX indicates: (Multiple Choice)
Question options:
A) silver brazing filler metals.
B) aluminum brazing filler metals.
C) copper brazing filler metals.
D) nickel and cobalt brazing filler metals.
Which of the following electrodes is used with DC electrode positive only? (Multiple Choice)
Question options:
A) E4311
B) E4310
C) E4918
D) E4928
B) E4310
Why does a hot rolled structural beam shape show compressive residual stresses at the edge of the flange? (Multiple Choice)
Question options:
A) Because it cools last
B) Because it cools first
C) Because the web pulls the flange into it
D) None of the above
B) Because it cools first
When automatic oxy-fuel gas cutting a strip from one edge of a plate distortion will occur. Why? (Multiple Choice)
Question options:
A) Uneven heating by automatic travel uniformly expands the cut edge
B) Uneven heating by automatic travel expands the edge next to the cut
C) Uneven heating by automatic travel contracts the edge next to the cut
D) Uneven heating by automatic travel shortens the edge next to the cut
C) Uneven heating by automatic travel contracts the edge next to the cut
There are several metallurgical phases in a steel depending on its carbon content and heating history. How is ferrite best described?
A) A complex phase that occurs above 723 °C
B) A phase that depends on fulfilling its structure by fast cooling
C) A solid solution in a face-centered cubic (FCC) phase of iron that dissolves only small amounts of carbon
D) A solid solution in a body-centred cubic (BCC) phase of iron that dissolves very small amounts of carbon
A) A complex phase that occurs above 723 °C
Molten steel contains dissolved oxygen, which tends to make steel brittle. An alloying element that can be added to reduce the amount of oxygen is: (Multiple Choice)
Question options:
A) nitrogen.
B) carbon.
C) aluminum.
D) sulphur
C) aluminum.
Grain size can influence the properties of steel in significant ways. What heat treatment is selected to improve the toughness of steel? (Multiple Choice)
Question options:
A) Normalizing reduces grain size to increase toughness
B) Annealing reduces grainsize to increase toughness
C) Quenching and then cold working increases the grain size to increase toughness
D) Tempering reduces the martensitic grain size to improve toughness
A) Normalizing reduces grain size to increase toughness
On a thin plate, the cooling rate is more sensitive to heat input and doubling the heat input will: (Multiple Choice)
Question options:
A) reduce the cooling rate four times.
B) reduce the cooling rate by half.
C) double the cooling rate.
D) not affect the cooling rate.
A) reduce the cooling rate four times.
Why is it possible for some multipass welds to have a higher toughness than a single pass weld? (Multiple Choice)
Question options:
A) The increased number of passes will increase the tensile strength
B) The increased number of passes will increase the yield strength
C) The passes in the multipass weld harden the underlying grain structure
D) The passes in the multipass weld refine the underlying grain structure
D) The passes in the multipass weld refine the underlying grain structure
Lamellar tearing is most likely to occur in which of the following? (Multiple Choice)
Question options:
A) Thick T-groove welds
B) T-groove welds in thin materials
C) Large groove welds
D) Groove welds in thin material
A) Thick T-groove welds
What are the critical parameters required to calculate energy input in a weld? (Multiple Choice)
Question options:
A) Volts, preheat and travel speed
B) Volts, amps, preheat, and efficiency
C) Volts, amps, and travel speed
D) Amps, travel speed, weave width, preheat, and efficiency
C) Volts, amps, and travel speed
With 8% nickel how much chromium must be added to produce austenitic stainless steel? (Multiple Choice)
Question options:
A) 10%
B) 14%
C) 18%
D) 22%
C) 18%
What best describes proof testing? (Multiple Choice)
Question options:
A) Tensile and creep testing
B) Electrostatic testing
C) Corrosion testing.
D) Overload testing
D) Overload testing
The uniform stress in a rod is given by the: (Multiple Choice)
Question options:
A) load multiplied by the cross-sectional area of the rod.
B) cross-sectional area of the rod divided by the load.
C) load divided by the cross-sectional area of the rod.
D) transverse load divided by the cross-sectional area of the rod.
C) load divided by the cross-sectional area of the rod.
Permanent set is: (Multiple Choice)
Question options:
A) the point just beyond UTS.
B) the amount of plastic deformation.
C) the elastic deformation minus the original length.
D) the yield elongation minus the ultimate tensile strength.
B) the amount of plastic deformation.
The type of magnetic lines of flux in prod magnetization is: (Multiple Choice)
Question options:
A) longitudinal with AC and circular with DC.
B) longitudinal with DC and AC.
C) circular with AC and DC.
D) elliptical with AC and DC.
C) circular with AC and DC.
