For the given two statements:I. The performance of an SI engine can be improved by increasing the compression ratio.II. Fuels of higher-octane numbers can be employed at a higher compression ratio.a)Both I and II are trueb)Both I and II are falsec)I is true, but II is falsed)I is false, but II is trueCorrect answer is option 'D'. Can you explain this answer?

EduRev

All Courses

Explore Courses UPSC Exam UPSC Test Series Free Notes EduRev Infinity

Open App

SSC Exam > SSC Questions > For the given two statements:I. The performa...

Join the Discussion on the App

For the given two statements:

I. The performance of an SI engine can be improved by increasing the compression ratio.

II. Fuels of higher-octane numbers can be employed at a higher compression ratio.

a)
Both I and II are true
b)
Both I and II are false
c)
I is true, but II is false
d)
I is false, but II is true

Correct answer is option 'D'. Can you explain this answer?

FREE This question is part of

SSC JE (ME) Mock Test - 2

Attempt Test

Attempt this Test

Verified Answer

For the given two statements:I. The performance of an SI engine can b...

The compression ratio of the engine also strongly affects knock. (The performance of an SI engine cannot be improved by increasing the compression ratio) The higher the compression ratio, the better the thermal efficiency but, the greater the tendency for knock to occur.

The critical compression ratio can be defined as the compression ratio when knock starts. So higher fuel octane quality is required (Fuels of higher-octane number can be employed at a higher compression ratio).

Important Point:

Knock occurs when the unburnt gases ahead of the flame front (the end gases) spontaneously ignite, causing a sudden rise in pressure accompanied by a characteristic pinging sound. This results in a loss of power and can lead to damage to the engine.

The antiknock value of an SI engine fuel is determined by comparing its antiknock property with a mixture of two reference fuels, iso-octane (C₈H₁₈) and normal heptane (C₇H₁₆).

Iso-octane, which has a very high resistance to knock and therefore is given an octane number of 100. Normal heptane, which has a very poor antiknock quality and is therefore given a zero value.

The octane number of fuels is defined as the percentage, by volume, of iso-octane in a mixture of iso-octane and normal heptane. A blend of 10% n-heptane and 90% iso-octane by volume has an octane number of 90.

Engines with low compression ratios can use fuels with lower octane numbers, but high compression engines must use high-octane fuel to avoid self-ignition and knock.

View all questions of this test

View all answers Start learning for free

< Previous Question Next Question >

Explore Courses for SSC exam

Similar SSC Doubts

Direction: In the following questions below are given some statements followed by some given conclusions. You have to take the given statements to be true even if they seem to be at variance with commonly known facts. Read all the conclusions and then decide which of the given conclusions logically follows from the given statements, disregarding commonly known facts. Give answer:Statements:Malpractices in the examination are the major cause of decline in the standards of education.Conclusions:I. To improve the standard of education, control on malpractices is necessary.II. These days, malpractices are happening in all the examinations.

View answer

Direction: In the following questions below are given some statements followed by some given conclusions. You have to take the given statements to be true even if they seem to be at variance with commonly known facts. Read all the conclusions and then decide which of the given conclusions logically follows from the given statements, disregarding commonly known facts. Give answer:Statements :(1): 60% of the government employees went on strike.(2) Mr. Gopal is a government employee.Conclusions:I : Mr. Gopal went on strike.II : Mr. Gopal did not participate in the strike.

View answer

Direction: In the following questions below are given some statements followed by some given conclusions. You have to take the given statements to be true even if they seem to be at variance with commonly known facts. Read all the conclusions and then decide which of the given conclusions logically follows from the given statements, disregarding commonly known facts. Give answer:Statements:Malpractices in the examination are the major cause of decline in education standards.Conclusions:I. To improve the standard of education, control on malpractices is necessary.II. These days, malpractices are happening in all the examinations.

View answer

Which of the following statements is wrong?

View answer

The volume of air delivered by the compressor is called

View answer

For the given two statements:I. The performance of an SI engine can be improved by increasing the compression ratio.II. Fuels of higher-octane numbers can be employed at a higher compression ratio.a)Both I and II are trueb)Both I and II are falsec)I is true, but II is falsed)I is false, but II is trueCorrect answer is option 'D'. Can you explain this answer?

Share with a Friend

Answer this doubt

Question Description
For the given two statements:I. The performance of an SI engine can be improved by increasing the compression ratio.II. Fuels of higher-octane numbers can be employed at a higher compression ratio.a)Both I and II are trueb)Both I and II are falsec)I is true, but II is falsed)I is false, but II is trueCorrect answer is option 'D'. Can you explain this answer? for SSC 2024 is part of SSC preparation. The Question and answers have been prepared according to the SSC exam syllabus. Information about For the given two statements:I. The performance of an SI engine can be improved by increasing the compression ratio.II. Fuels of higher-octane numbers can be employed at a higher compression ratio.a)Both I and II are trueb)Both I and II are falsec)I is true, but II is falsed)I is false, but II is trueCorrect answer is option 'D'. Can you explain this answer? covers all topics & solutions for SSC 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for For the given two statements:I. The performance of an SI engine can be improved by increasing the compression ratio.II. Fuels of higher-octane numbers can be employed at a higher compression ratio.a)Both I and II are trueb)Both I and II are falsec)I is true, but II is falsed)I is false, but II is trueCorrect answer is option 'D'. Can you explain this answer?.

Solutions for For the given two statements:I. The performance of an SI engine can be improved by increasing the compression ratio.II. Fuels of higher-octane numbers can be employed at a higher compression ratio.a)Both I and II are trueb)Both I and II are falsec)I is true, but II is falsed)I is false, but II is trueCorrect answer is option 'D'. Can you explain this answer? in English & in Hindi are available as part of our courses for SSC. Download more important topics, notes, lectures and mock test series for SSC Exam by signing up for free.

Here you can find the meaning of For the given two statements:I. The performance of an SI engine can be improved by increasing the compression ratio.II. Fuels of higher-octane numbers can be employed at a higher compression ratio.a)Both I and II are trueb)Both I and II are falsec)I is true, but II is falsed)I is false, but II is trueCorrect answer is option 'D'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of For the given two statements:I. The performance of an SI engine can be improved by increasing the compression ratio.II. Fuels of higher-octane numbers can be employed at a higher compression ratio.a)Both I and II are trueb)Both I and II are falsec)I is true, but II is falsed)I is false, but II is trueCorrect answer is option 'D'. Can you explain this answer?, a detailed solution for For the given two statements:I. The performance of an SI engine can be improved by increasing the compression ratio.II. Fuels of higher-octane numbers can be employed at a higher compression ratio.a)Both I and II are trueb)Both I and II are falsec)I is true, but II is falsed)I is false, but II is trueCorrect answer is option 'D'. Can you explain this answer? has been provided alongside types of For the given two statements:I. The performance of an SI engine can be improved by increasing the compression ratio.II. Fuels of higher-octane numbers can be employed at a higher compression ratio.a)Both I and II are trueb)Both I and II are falsec)I is true, but II is falsed)I is false, but II is trueCorrect answer is option 'D'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice For the given two statements:I. The performance of an SI engine can be improved by increasing the compression ratio.II. Fuels of higher-octane numbers can be employed at a higher compression ratio.a)Both I and II are trueb)Both I and II are falsec)I is true, but II is falsed)I is false, but II is trueCorrect answer is option 'D'. Can you explain this answer? tests, examples and also practice SSC tests.

Explore Courses for SSC exam