Mechanical Engineering MCQs

Page No. 139

For proper refrigeration in a cabinet, if the temperature and vapour pressure difference between cabinet and atmosphere is high, then_________________?


abigger cabinet should be used

✖


bsmaller cabinet should be used

✖


cperfectly tight vapour seal should be used

✓


drefrigerant with lower evaporation temperature should be used

✖



The advantage of dry compression is that________________?


ait permits higher speeds to be used

✖


bit permits complete evaporation in the evaporator

✖


cit results in high volumetirc and mechanical efficiency

✖


dall of the above

✓


View Answer all of the above

The suction pipe diameter of refrigerating unit compressor in comparison to delivery side is_________________?


abigger

✓


bsmaller

✖


cequal

✖


dsmaller/bigger depending on capacity

✖


View Answer bigger

Under-cooling in a refrigeration cycle_________________?


aincreases COP

✓


bdecreases COF

✖


cCOP remains unaltered

✖


dother factors decide COP

✖


View Answer increases COP

The coefficient of performance is the ratio of the refrigerant effect to the_________________?


aheat of compression

✖


bwork done by compressor

✖


centhalpy increase in compressor

✖


dall of the above

✓


View Answer all of the above

Vertical lines on pressure-enthalpy chart show constant_______________?


apressure lines

✖


btemperature lines

✖


ctotal heat lines

✓


dentropy lines

✖


View Answer total heat lines

The general rule for rating refrigeration systems (excepting for C02 system) is to approximate following h.p. per ton of refrigeration__________________?


a0.1 to 0.5 h.p. per ton of refrigeration

✖


b0.5 to 0.8 h.p. per ton of refrigeration

✖


c1 to 2 h.p. per ton of refrigeration

✓


d2 to 5 h.p. per ton of refrigeration

✖



Cooling water is required for following equipment in ammonia absorption plant__________________?


acondenser

✖


bevaporator

✖


cabsorber

✖


dcondenser, absorber and separator (rectifier)

✓



The C.O.P. of a refrigeration cycle with lowering of condenser temperature, keeping the evaporator temperature constant, will__________________?


aincrease

✓


bdecrease

✖


cmay increase or decrease depending on the type of refrigerant used

✖


dremain unaffected

✖


View Answer increase

The evolution of heat of solution takes place in ammonia absorption plant when _____________________?


aammonia vapour goes into solution

✓


bammonia vapour is driven out of solution

✖


clithium bromide mixes with ammonia

✖


dweak solution mixes with strong solution

✖



Goto Page No.

Page 139 of 190

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