20751. While the total emissivity of a perfect black body is unity, the same for a real body is
20752. The Grashoff number is defined as the ratio of the
20753. According to Reynolds analogy, Stanton number is equal to (where, f = Fanning friction factor)
20754. The absorptivity of a body is equal to its emissivity
20755. Absorptivity and refletivity of a perfect black body are respectively
20756. In thermal radiation for a black body (where, ε is emissivity and α is absorptivity)
20757. Which of the following Fundamental Rights has been deleted by 44th amendment bill?
20758. When warm and cold liquids are mixed, the heat transfer is mainly by
20759. A cube, sphere & a thin circular plate (all having same mass and made of same material) are all heated to 300°C and allowed to cool in natural air. Which one will cool the slowest ?
20760. Vent pipes are provided in a condenser to
20761. Heat transfer by natural convection is enhanced in system with
20762. In case of __________ boiling, the bubbles formed on a submerged hot surface get absorbed in the mass of the liquid.
20763. A body cools down from 75°C to 70°C in 10 minutes. It will cool down from 70° C to 65° C in __________ minutes.
20764. In forced convection, the Nusselt number is a function of
20765. At what value of Prandtl number, the hydrodynamic and thermal boundary layers are identical ?
20766. A dilute aqueous solution is to be concentrated in an evaporator system. High pressure steam is available. Multiple effect evaporator system is employed, because
20767. Heat transfer efficiency leading of energy conservation in a heat exchanger can be achieved by
20768. Trap is used to remove __________ from steam pipe lines.
20769. A composite flat wall of a furnace is made of two materials 'A' and 'B'. The thermal conductivity of 'A' is twice of that of material 'B', while the thickness of layer of 'A' is half that of B. If the temperature at the two sides of the wall are 400 and 1200°K, then the temperature drop (in °K) across the layer of material 'A' is
20770. Tube pitch is the __________ of tube diameters and the clearances.
20771. With increase in the distance between the heat source and the object receiving the heat, the radiation heat transfer
20772. The equivalent diameter for the annulus of a double pipe heat exchanger, whose inner pipe has fins on the outside is __________ compared to the same size pipes without fins.
20773. Natural convection is characterised by
20774. Nusselt number for full developed, laminar, constant property flow in a pipe at uniform heat flux is
20775. Thickness of thermal boundary layer is more compared to that of hydrodynamic boundary layer, when the value of Prandtl number is
20776. The critical radius of insulation for cylindrical pipe is (where, hi = heat transfer coefficient at inside of the pipe )
20777. The heat flux in the nucleate boiling regimes is proportional to (where, ΔT = excess temperature)
20778. In a 1-1 cocurrent heat exchanger, if the tube side fluid outlet temperature is equal to the shell side fluid outlet temperature, then the LMTD is
20779. A body is called grey if the monochromatic emissivity of the body is
20780. In an extended surface heat exchanger, fluid having lower co-efficient
20781. In a shell and tube heat exchanger, the tube side heat transfer co-efficient just at the entrance of the tube is
20782. Grashoff number, which is defined as g . β(Ts - T∞) ρ2. L3/μ2, is proportional to the ratio of buoyancy force to __________ force.
20783. Who was the first Harijan member of Srimoolam Prajasabha?
20784. Hitler was appointed Cheancellor of Germany in?
20785. For a cold dilute feed to produce thick viscous liquor, backward feeding as compared to forward feeding results in
20786. Economy of an evaporator is influenced by the
20787. If the thermal conductivity of a wall material is independent of temperature, the steady state temperature distribution in the very large thin plane wall having steady, uniform surface temperature follows __________ law.
20788. In regenerative air preheater (as practised in heating of coke ovens), the heat is transferred
20789. __________ equation relates the thermal conductivity of a solid to its temperature.
20790. For small temperature difference, the heat transfer rate as per Newton's law of cooling is proportional to (where, Δt = excess temperature)
20791. English is the official language of which of the following state?
20792. Viscous & heat sensitive liquids are concentrated in __________ evaporators.
20793. 1 BTU/hr.ft.°F is equal to __________ kcal/hr. m.°C.
20794. Heat transfer by radiation between two bodies at T1 & T2 and in an ambient temperature of Ta°C depends on
20795. The ratio of momentum diffusivity to thermal diffusivity is the __________ number.
20796. For a perfectly transparent surface (like gases), the
20797. For a fluid flowing in an annulus space, the wetted perimeter for heat transfer and pressure drop are
20798. During crystallisation, formation of crystal can occur in __________ solution only.
20799. An evaporator while concentrating an aqueous solution from 10 to 40% solids evaporates 30000 kg of water. The amount of solids handled by the system in kg is