1487. Radiant energy received by a body is proportional to (where, d = the distance between the object emitting radiation and that receiving it.)
√d
d
d2
d1.5
✅ The correct answer is option C.
1450. A sphere of radius ‘R₁’ is enclosed in a sphere of radius ‘R₂’. The view (or shape) factor for radiative heat transfer of the outer sphere with respect to the inner sphere is
0
R₂/(R₁+R₂)
1
(R₁/R₂)2
✅ The correct answer is option B.
1453. Maximum heat transfer rate is achieved in __________ flow.
Co-current
Counter-current
Turbulent
Laminar
✅ The correct answer is option C.
1456. ‘Fouling factor’ used in the design of a multipass shell and tube heat exchanger is a
Non-dimensional factor
Factor of safety
Conversion factor for individual film heat transfer co-efficient to overall heat transfer co-efficient
None of these
✅ The correct answer is option B.
1459. Prandtl and Reynolds analogy are same, when Prandtl number is
0.5
1
> 2
1.5
✅ The correct answer is option B.
1462. Steam is routed through the tube in case of a __________ evaporator.
Basket type
Horizontal tube
Short tube vertical
Long tube vertical
✅ The correct answer is option B.
1465. A multiple effect evaporator has a capacity to process 4000 kg of solid caustic soda per day, when it is concentrating from 10% to 25% solids. The water evaporated in kg per day is
6000
24000
60000
48000
✅ The correct answer is option B.
1468. The Grashoff number is defined as the ratio of the
Buoyancy to inertial forces
Buoyancy to viscous forces
Inertial to viscous forces
Buoyancy to surface tension forces
✅ The correct answer is option B.
1471. Heat transfer by __________ may not necessarily require the presence of a medium.
Conduction
Natural convection
Forced convection
Radiation
✅ The correct answer is option D.
1474. LMTD for counterflow and prallel flow heat exchanger will be the same, when the
Cold fluid is heated to a certain temperature by condensing steam (isothermal fluid)
Outlent temperature of both the hot and cold fluid are same
Outlet temperature of hot fluid is less than the outlet temperature of the cold fluid
None of these
✅ The correct answer is option A.