374. A spring material should have low
A. Elastic limit
B. Deflection value
C. Fatigue resistance
D. None of these
✅ The correct answer is option D.
376. Function of blow down valve in a boiler is to
A. Maintain the drum level
B. Keep the drum pressure constant
C. Drain out the sludge from the drum
D. Empty the boiler during shutdown
✅ The correct answer is option C.
378. Gross & Net calorific values will be the same for
A. Methane
B. Propane
C. Carbon monoxide
D. Hydrogen
✅ The correct answer is option C.
342. Fatigue strength of a metal is improved by
A. Overstressing
B. Scratching the surface
C. Raising the temperature
D. Understressing
✅ The correct answer is option D.
344. Cast iron contains __________ percent carbon.
A. 2.5
B. 3.75
C. 4.75
D. 5.25
✅ The correct answer is option A.
346. Eutectoid composition of carbon steel at room temperature is
A. Cementite
B. Pearlite
C. Martensite
D. Ferrite
✅ The correct answer is option B.
348. Normalising of a casting does not
A. Induce stresses in it
B. Refine its grain structure
C. Reduce seggregation
D. Improve its mechanical properties
✅ The correct answer is option A.
350. For separating small pieces of metal from engine oil of a car, the best separating technique is the
A. Chromatography
B. Evaporation
C. Filtration
D. Fractional distillation
✅ The correct answer is option C.
352. Nitrogen compounds are not used in the manufacture of
A. Fertilisers
B. Gun powder
C. Tip of match sticks
D. Explosive
✅ The correct answer is option C.
354. Springback in sheet metal bending depends on the
A. Elastic limit
B. Bend radius
C. Degree of bend
D. Thickness of sheet
✅ The correct answer is option D.