A. Hardness
B. Dissolved solids content
C. Suspended solids content
D. All A., B. and C.
Correct Answer: D. All A., B. and C. ✔
Last Updated: March 03, 2019
Related MCQs
- __________ paint has the maximum absorption coefficient ?
- Baffles are provided in heat exchangers to increase the__________?
- Prandtl and Reynold’s analogies are identical for Prandtl number value of__________?
- The rate of heat transfer through a pipe wall is given by, q = 2π k (Ti – T0)/ln (ri/r0). For cylinder of very thin wall, q can be approximated by__________?
- If a single tube pass heat exchanger is converted to two pass, then for the same flow rate, the pressure drop per unit length in tube side will __________?
- A measure of the extent to which viscous heating is important relative to the heat flow resulting from the impressed temperature difference is represented by the __________ number?
- Heat transfer efficiency leading of energy conservation in a heat exchanger can be achieved by__________?
- Which is the most suitable for the concert-ration of highly concentrated solution ?
- A hot liquid is kept in a big room. The logarithm of the numerical value of the temperature difference between the liquid and the room is plotted against time. The plot will be very nearly a/an__________?
- A hot body will radiate heat most rapidly, if its surface is__________?
- Prandtl number is the ratio of__________?
- Rate of heat transfer by vaporisation from pools of water is affected by the __________?
- The purpose of providing bleed points in the evaporator is to__________?
- With increase in temperature, the thermal conductivity of steel__________?
- In a shell and tube heat exchanger, the tube side heat transfer co-efficient just at the entrance of the tube is__________?
- Which of the following is the most controlling factor for the rate of bubble detachment from the hot solid surface ?
- Radiation heat transfer rates does not depend upon the__________?
- If all the conditions and dimensions are same, then the ratio of velocity through the tubes of a double pass heat exchanger to that through the single pass heat exchanger is__________?
- Which of the following is not concerned with the heat transfer ?
- __________ equation relates the thermal conductivity of a solid to its temperature ?
- Unsteady state heat conduction occurs, when__________?
- For specified tube outside diameter, higher BWG means higher__________?
- A long iron rod initially at a temperature of 20°C has one end dipped in boiling water (100°C) at time, t = 0. The curved surface of the rod is insulated so that heat conduction is one dimensional in the axial direction. The temperature at a distance 100 mm from the dipped end becomes 40°C at time, t = 200 s. The same temperature is achieved at a distance of 200 mm from the dipped end at time __________?
- Value of Prandtl number for water ranges from__________?
- For a fluid flowing in an annulus space, the wetted perimeter for heat transfer and pressure drop are__________?
- 1000 kg of wet solids are to be dried from 60% to 20% moisture (by weight). The mass of moisture removed in kg is__________?
- Dropwise condensation occurs on __________ surfaces?
- Conduction occurs in the buffer zone for a fluid flowing through a heated pipe, only when Prandtl number is__________?
- The type of liquor circulation system to be ‘ employed in evaporators (viz. natural or forced circulation) is determined mainly by the __________ of the liquid?
- For a given ambient air temperature with increase in the thickness of insulation of a hot cylindrical pipe, the rate of heat loss from the surface would ?
- In a backward feed multiple effect evaporator __________ ?
- The sum of reflectivity and absorptivity for an opaque body is equal to__________?
- Steam is routed through the tube in case of a __________ evaporator?
- Multiple effect evaporation is generally recommended, when the__________?
- 1 BTU/hr.ft.°F is equal to __________ kcal/hr. m.°C?
- A __________ surface has the maximum thermal emissivity out of the following ?
- A hollow sphere and a solid sphere of the same material and equal radii are heated to the same temperature. In this case ?
- Which of the following has the highest thermal conductivity ?
- Circulation pump is located below the evaporator to__________?
- Economy of an evaporator is influenced by the__________?
- ‘Fouling factor’ used in the design of a multipass shell and tube heat exchanger is a__________?
- At Pr > 1, conduction in an ordinary fluid flowing through a heated pipe is limited to the__________?
- Film boiling occurs at __________ pressure?
- Choose the most important factor on which the heat conducted through a wall in a unit time will depend on ?
- Thickness of thermal boundary layer is more compared to that of hydrodynamic boundary layer, when the value of Prandtl number is__________?
- Double pipe heat exchangers are preferably useful, when__________?
- With increase in the distance between the heat source and the object receiving the heat, the radiation heat transfer ?
- For gases, the thermal conductivity increases with temperature rise. For liquids, with increase in concentration, its thermal conductivity generally ?
- For a counter current heat exchanger with Ti h = 80°C, T°c = 60°C, T°h = 50°C and Ti c = 30°C, and the temperature difference between the two streams being the same everywhere along Z, the direction of flow of hot fluid. The temperature profile should satisfy__________?
- Heat flux through several resistances in series in analogous to the current flowing through several__________?
- At what value of Prandtl number, the hydrodynamic and thermal boundary layers of a fluid flowing over a heated plate will be identical ?