3865. Which of the following radiations is the least penetrating ?
α-rays
β-rays
γ-rays
X-rays
✅ The correct answer is option A.
3870. Solar energy results from __________ reaction.
fission
combustion
thermonuclear
none of these
✅ The correct answer is option C.
3874. The time required for half of the __________ of a radioactive isotope to decay is called its half life.
nuclei
electrons
protons
neutrons
✅ The correct answer is option A.
3880. The type of pump used for the recirculation of molten sodium coolant in liquid metal cooled reactor is a/an __________ pump.
electromagnetic
reciprocating
centrifugal
volute
✅ The correct answer is option A.
3885. An underdesigned steam trap will
waste steam.
destroy itself of acceleration wear due to rapid recycling.
back up condensate and cause water hammer in steam line.
none of these.
✅ The correct answer is option C.
3891. Minimum recommended baffle spacing in a shell and tube heat exchanger is about (where, D = shell diameter )
0.2 D
0.5 D
0.66 D
0.80 D
✅ The correct answer is option A.
3897. Equivalent diameter for heat transfer calculation for a duct of square cross-section having each side as ‘d’ will be
d
d
2πd
2d
✅ The correct answer is option A.
3862. At the following point for a given packing and set of fluids, the pressure drop per metre of packed height, with variation in fluid rates and operating pressure
increases
decreases
remains same
may increase or decrease depending upon the solubility of the gas in the liquid
✅ The correct answer is option C.
3866. In actual operation of a bubble cap distillation tower, the __________ at the bottom of the tower is more than that at the top of the tower.
molal flow rate of vapour
vapour molecular weight
pressure and temperature
all (a), (b) and (c)
✅ The correct answer is option D.
3868. Pick out the wrong statement about distillation operation
Distillation under vacuum is a substitute for steam distillation.
In differential (simple) distillation, the vapour is removed as soon as it is formed without appreciable condensation.
In flash (equilibrium) distillation, a definite fraction of liquid is vaporised in such a way that the evolved vapour & residual liquids are in equilibrium with each other.
Flash distillation, differential distillation & steam distillation are all continuous distillation processes.
✅ The correct answer is option D.