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Questions (43 - 49)
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In this lesson, questions (43 -49) 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

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  1. COURSE: Questions on Steam Turbine Lesson : Questions-(43-49)


  2. About me Graduated from NIT Nagpur in 2008 A. 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: https://unacademy.in/user/harshit aggarwal


  3. Question 43 Steam Pressure Velocity The pressure and velocity diagram as shown in the figure above for a steam turbine refers to which one of the following: (Where: M-moving blade, F-fixed-blade) (a) Impulse turbine-Velocity compounded (b) Impulse turbine-Pressure compounded (c) Impulse turbine-Pressure and Velocity compounde<d (d) Reaction turbine stages Ans d


  4. Question 44 The graph given in the figure represents the variation absolute velocity of steam along the length of a steam turbine. The turbine in question is (a) Curtis turbine (b) De Leval turbine (c) Radial turbine (d) Parson's turbine Distance from nlet


  5. Question 45 Which one of the following relationship between angles of fixed blades and moving blades corresponds to that of Parson's turbine? (a) , - (c)a, p (d) B-P2 Ans b


  6. Question 46 In a 50% reaction stage, absolute velocity angle at inlet is 450 mean peripheral speed is 75 m/s and the absolute velocity at the exit is axial. The stage specific work is (a) 2500 m2/s2 (b) 3270 m2/s2 (c) 4375 m2/s2 (d) 5625 m2/s2


  7. Solution 46 For 50% reaction stage, inlet and outlet velocity stages are equal specific work- V,V, Ans d


  8. Question 47 For a reaction turbine with degree of reaction equal to 50%, (V is the absolute steam velocity at inlet and a. is the angle made by it to the tangent on the wheel) the efficiency is maximum when the blade speed is equal to (a)V cosa/2 (b) 2V cos (c) Vcos a (d) V cos Ans d


  9. Question 48 For maximum blade efficiency (utilization factor), what is the work (J/kg) done in a single stage 50% reaction turbine? (a) 2u2 (b) 1/u2 (c) u3 (d) u2 Ans d


  10. Question 49 Assertion (A): work output per stage of an impulse turbine is double that of a 50% reaction stage at the same speed Reason (R): Maximum speed ratio is limited for any class of turbine. (a) Both A and R are individually true and R is the correct explanation of A (b) Both A and R are individually true but R is not the correct explanation of A (c) A is true but R is false (d) A is false but R is true Ans : d