RRB JUNIOR ENGINEERS (MECHANICAL ENGINEERING) PREVIOUS EXAMS QUESTIONS

1. A feeler gauge is used to check

a. Radius

b. Screw pitch

c. Surface roughness

d. Unsymmetrical shape

e. Thickness of clearance

Ans :: e

 

2. The possibility of negative slip in reciprocating pump is when

(a) delivery pipe is short

(b) suction pipe is long

(c) pump is running at high speed

(d) all of the above

Ans:- D

3. A single acting reciprocating pump, running at 60 r.p.m, delivers 0.01 m2/sec of water. The area of the piston is 0.05m2 and stroke length is 40 cm. Then theoretical discharge of the pump will be

(a) 0.015 m3/sec

(b) 0.02 m3/sec

(c) 0.025 m3/sec

(d) 0.03 m3/sec

Ans:- B 

 

4.  In question (A), the co-efficient of discharge would be

(a) 0.9

(b) 0.8

(c) 0.6

(d) 0.5

Ans:- D

 

5. In question (A), the slip of the pump would be

(a) 0.02 m3/sec

(b) 0.01 m3/sec

(c) 0.005 m3/sec

(d) 0.003 m3/sec

Ans:- B

  

6. The impact strength of an material is an index of its

a. Toughness

b. Tensile strength

c. Capability of being cold worked

d. Hardness

e. Fatigue strength

Ans :: a

 

7. The slip in the reciprocating pump will be negative if

(a) Qth > Qact

(b) Qth < Qact

(c) Qth = Qact

(d) none of the above

Ans:- B