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13 lessons,
1h 53m
Questions (1-6)
1,376 plays

In this lesson, questions (1-6) have been discussed

Harshit Aggarwal
Cleared UPSC ESE twice with Rank 63 and 90 in mechanical engg. Got 99 percentile in GATE. Cracked ONGC, BHEL,ISRO, SAIL, GAIL successfully

Unacademy user
in the qstn 1, Q2 is the heat rejected, right? then its answer is 16.67...???
In Q.1, the correct option is 'option a' right?
sir, in ans. 6, there is wrong formula of efficiency.
  1. COURSE: Question on I C Engine Lesson: Question (1-6)

  2. About me Graduated from NIT Nagpur in 2008 Cleared Engineering Services Examination (ESE-UPSC) Exam Got the offer letter from most of the Maharatna and Navratna Companies Cleared GATE Exam Rate, Review, Recommend, Share Follow me on Unacademy at: aggarwal

  3. Question 1 A cyclic heat engine does 50 kJ of work per cycle. If the efficiency of the heat engine is 75%, the heat rejected per cycle is (a)16kJ(b)33k (c)372 kJ (d)66 kJ

  4. Solution 1 50 or 0.75 or Q,66.67kJ Q, W-Q-Q or Q2-66.67-50-10%kJ Ans : d

  5. Question 2 A Carnot cycle is having an efficiency of 0.75. If the temperature of the high temperature reservoir is 7270 C/ what is the temperature of low temperature reservoir? (a) 23 C (b) -23 C (c) 0 C (d) 250 C

  6. Solution 2 T. T, T, (273-727) (273+727) 1-minor 0.75 1 ..Tmin-250K--23 C cannot Ans: b

  7. Question 3 A solar energy based heat engine which receives 80 kJ of heat at 100 deg C and rejects 70 kJ of heat to the ambient at 30 deg C is to be designed. The thermal efficiency of the heat engine is (a) 70% (b) 1.88% (c) 12.5% (d) indeterminate

  8. Solution3 Q,-Q2 a, 70 80 Ans : C

  9. Question 4 A cycle consisting of two reversible isothermal processes and two reversible isobaric processes is known as (a) Atkinson cycle (c) Brayton cycle (b) Stirling cycle (d) Ericsson cycle Ans d

  10. Question 5 Which one of the following is NOT a necessary assumption for the air standard Otto cycle? (a) All processes are both internally as well as externally reversible. (b) Intake and exhaust processes are constant volume heat rejection processes (c) The combustion process is a constant volume heat addition process. (d) The working fluid is an ideal gas with constant specific heats. Ans :b

  11. Solution 6 Swept Volume V - 2 x L= mx (0.1)2 0.15m3-1.1781 10-3 m3 4 4 Final Volume (v2) - 196.3 cc 0.1963 x 10-3 m3Ve Compression Ratio = (Vs + Vc) /Vc = 1-ry-1 = 1-714-1 = 0.5408 w = Q = 0.5408 x 1800 = 973.5 kJ Ans d