Mechanical Engineering MCQs

Page No. 55

According to Recardo’s theory, detonation occurs due to______________________?


ainstantaneous auto-ignition of last part of charge to be burnt


bimproper mixing of air and fuel


cimproper combustion


dself ignition temperature has nothing to do with detonation



The knocking in diesel engines for given fuel, will be__________________?


aenhanced by increasing compression ratio


benhanced by decreasing compression ratio


cunaflected by compression ratio


dfirst enhanced by increasig compression ratio upto a limit beyond which it will be suppressed



Injection lag is_________________?


athe time taken by fuel after injection (before top dead center) to reach upto auto-ignition temperature


btime before actual fuel injection and the pump pluger starts to pump fuel


ctime corresponding to actual injection and top dead center


dtime corresponding to actual ignition and top dead center



Carbon residue in diesel oil should not be more than___________________?


a1%


b0.5%


c0.1%


d0.001%


View Answer 0.001%

Diesel engines have low specific fuel consumption compared to petrol engine. This statement is____________________?


anot true


btrue at full load


ctrue at part load


dtrue at both part and full load



In order to prevent knock in the S.I. engines, the charge away from the spark plug should have___________________?


alow temperature


blow density


clong ignition delay


dall of the above


View Answer all of the above

To reduce the possibility of knock in the C.I. engines, the first elements of fuel and air should have_______________?


ahigh temperature


bhigh density


cshort delay


dall of the above


View Answer all of the above

Piston rings are plated with chromium,cadmium or phosphate in order to__________________?


areduce cost


bimprove surface finish


cprevent clogging


dreduce wear and eliminate scuffing



The pistons are usually given a coating such as tin plating in order to________________?


areduce weight


bconduct heat efficiently


creduce possibility of scoring


dreduce friction



If overhead clearance is less, then the following type of engine should be selected__________________?


aV-type


bIn-line


cVertical


dHorizontal


View Answer Horizontal

Goto Page No.

Page 55 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