Chemical Engineering MCQs

Page No. 457

Nusselt number is the ratio of the ____________________?


aTemperature gradient of the wall to that across the entire pipe


bTemperature difference to the temperature gradient at the wall


cHeat flux at the wall to that across the entire pipe


dNone of these



Prandtl number is the reciprocal of____________________?


aThermal diffusivity/Momentum diffusivity


bThermal diffusivity × Momentum


cThermal diffusivity × Mass diffusivity


dMass diffusivity × Momentum diffusivity



For a multipass shell and tube heat exchanger, the LMTD correction factor is always________________?


a1


b> 1


c< 1


dBetween 1 & 2


View Answer < 1

Thermal conductivity of a gas at low density, ___________ with increase in temperature ?


aDecreases


bIncreases


cRemains unchanged


dMay increase or decrease; depends on the gas


View Answer Increases

The interchange factor for radiation heat transfer from surface ‘x’ to surface ‘y’ in case of an infinite parallel planes with emissivities εx & εy is given by_______________?


aεx + εy


bεx . εy


c1/εx + 1/εy


d(εx + εy)/( εx + εy – εx . εy)



With increase in temperature, the thermal conductivity of a gas ___________________?


aIncreases


bDecreases


cRemain same


dMay increase or decrease depending on the type of gas


View Answer Increases

Which area is used in case of heat flow by conduction through a cylinder ?


aLogarithmic mean area


bArithmetic mean area


cGeometric mean area


dNone of these


View Answer Logarithmic mean area

The rate of emission of radiation by a body does not depend upon the__________________?


aWavelength of radiation


bSurface temperature of the body


cNature of the surface


dShape and porosity of the body



In a cooling tower, water becomes cool by________________?


aLoosing sensible heat


bHeat transfer to surroundings


cVaporisation due to heat loss to air


dLoosing latent heat


View Answer Loosing sensible heat

Out of the following four assumptions used in the derivation of the equation for LMTD [LMTD = (Δt1 – Δt2)/ln(Δt1/Δt2)], which one is subject to the largest deviation in practice ?


aConstant overall heat transfer co-efficient.


bConstant rate of fluid flow


cConstant specific heat


dNo partial phase change in the system



Goto Page No.

Page 457 of 843

Alphabetical MCQs Categories

Here below You find all kind of categories of MCQs in alphabetical order.


"Comprehensive Collection of MCQs: Alphabetically Organized by Subject"

"Discover an extensive collection of multiple-choice questions (MCQs) neatly categorized by subject from A to Z. This resource is designed for anyone eager to explore various topics in a straightforward and organized manner. Whether you're a student preparing for exams, an educator seeking supplementary materials, or simply curious about different subjects, this compilation offers a convenient way to learn and assess your knowledge. With questions arranged alphabetically, navigation is effortless, allowing you to delve into subjects of interest at your own pace. Engage, learn, and expand your understanding with this accessible and comprehensive repository of MCQs!"


BolPakistan

bolpakistan.com.pk includes Job Mcqs and Pak Mcqs is the Top Largest Mcqs Forum in World, in which you can read Mcqs of All Subjects, PPSC test preparation, FPSC, NTS and PPSC PAST PAPERS, PPSC PAST MCQS. A Collection of Repeated MCQs for JOBs seekers.

Copyright © 2024, Designed & Developed by BolPakistan