Otto Cycle - MCQs with Answers
Q1. Otto cycle is the air standard cycle ofa. spark ignition (SI) engine
b. compression (CI) ignition engine
c. both SI and CI engines
d. none of the above
View Answer / Hide Answer ANSWER: a. spark ignition (SI) engine
Q2. How is the heat added in the Otto cycle?a. reversibly at constant pressure
b. irreversibly at constant pressure
c. reversibly at constant volume
d. irreversibly at constant volume
View Answer / Hide Answer ANSWER: c. reversibly at constant volume
Q3. What is the formula for compression (rk) ratio of the Otto cycle?a. r
k = Volume of cylinder at the beginning of compression / Volume of cylinder at the end of compression
b. r
k = Volume of cylinder at the end of compression / Volume of cylinder at the beginning of compression
c. r
k = Volume of cylinder at the end of compression / clearance volume
d. none of the above
View Answer / Hide Answer ANSWER: a. rk = Volume of cylinder at the beginning of compression / Volume of cylinder at the end of compression
Q4. What is the relation between compression ratio (rk) and the efficiency of the Otto cycle?a. efficiency decreases with increase in compression ratio
b. efficiency increases with increase in compression ratio
c. efficiency does not affected by change in compression ratio
d. none of the above
View Answer / Hide Answer ANSWER: b. efficiency increases with increase in compression ratio
Q5. The compression ratio cannot be increased beyond certain limit, because it results toa. auto-ignition of fuel
b. detonation
c. engine knocking
d. all of the above
View Answer / Hide Answer ANSWER: d. all of the above
Q6. What should be the correct graph for effect of compression ratio (rk) on cycle efficiency?a.
b.
c.
d.
View Answer / Hide Answer ANSWER: d.
Q7. Use of gasoline blend like gasoline mixed with tetraethyl lead in internal combustion enginea. increases the octane rating of the fuel
b. allows engine to operate at higher compression ratio
c. avoids auto-ignition of fuel
d. all of the above
View Answer / Hide Answer ANSWER: d. all of the above
Q8. How is the efficiency of the SI engine affected by change in specific heat ratio (γ) of the working fluid?a. the efficiency of the engine increases with increase in specific heat ratio (γ) of the working fluid
b. the efficiency of the engine decreases with increase in specific heat ratio (γ) of the working fluid
c. the efficiency of the engine does not affected by change in specific heat ratio (γ) of the working fluid
d. none of the above
View Answer / Hide Answer ANSWER: a. the efficiency of the engine increases with increase in specific heat ratio (γ) of the working fluid