Machine Design Mechanical Engineering Questions - Set 31 - ObjectiveBooks

# Practice Test: Question Set - 31

1. In designing a sleeve coupling, length of the sleeve is taken as (where d = Diameter of the shaft)
(A) d + 17 mm
(B) 2d + 13 mm
(C) 2d + 20 mm
(D) 3.5 d

2. The maximum shear stress theory is used for
(A) Brittle materials
(B) Ductile materials
(C) Plastic materials
(D) Nonferrous materials

3. A circular shaft can transmit a torque of 5 kN-m. If the torque is reduced to 4 kN-m, then the maximum value of bending moment that can be applied to the shaft is
(A) 1 kN-m
(B) 2 kN-m
(C) 3 kN-m
(D) 4 kN-m

4. In worm, gears, pitch lead angle is
(A) Half the angle between two inclined faces in axial plane
(B) The angle between the tangent to the pitch helix and the plane of rotation
(C) The angle between the tangent to the pitch helix and an element of the cylinder
(D) None of the above

5. In designing a connecting rod, it is considered like __________ for buckling about X-axis.
(A) Both ends hinged
(B) Both ends fixed
(C) One end fixed and the other end hinged
(D) One end fixed and the other end free

6. Two rigid plates are clamped by means of bolt and nut with an initial force F. After tightening, a separating force P (P < F) is applied to the lower plate, which in turn acts on the nut. The tension in the both after this is
(A) F + P
(B) F.P
(C) P
(D) F

7. The spring mostly used in gramophones is
(A) Helical spring
(B) Conical spring
(C) Flat spiral spring
(D) Volute spring

8. The maximum bending stress in a curved beam having symmetrical section always occur at the
(A) Centroidal axis
(B) Neutral axis
(C) Inside fiber
(D) Outside fiber

9. In a flange coupling, the bolts are subjected to
(A) Tensile stress
(B) Compressive stress
(C) Shear stress
(D) None of these

10. The ratio of circumferential stress to longitudinal stress in a thin cylinder subjected to an internal pressure is
(A) 1/2
(B) 1
(C) 2
(D) 4

11. For a shoe brake, the equivalent coefficient of friction is equal to (where μ = Actual coefficient of friction, and θ = Semi-block angle)
(A) 2μ sinθ/(θ + sinθ)
(B) μ sinθ/(2θ + sin 2θ)
(C) 4μ sinθ/(θ + sinθ)
(D) 4μ sinθ/(2θ + sin 2θ)

12. When a hole of diameter ‘d’ is punched in a metal of thickness 't', then the force required to punch a hole is equal to (where τu = Ultimate shear strength of the material of the plate)
(A) d.t.τu
(B) πd.t.τu
(C) π/4 × d².τu
(D) π/4 ××u

(A) Brittle materials
(B) Ductile materials
(C) Brittle as well as ductile materials
(D) Elastic materials

14. Which of the following statement is correct, for two shafts connected in parallel?
(A) Torque in each shaft is the same
(B) Shear stress in each shaft is the same
(C) Angle of twist of each shaft is the same
(D) Torsional stiffness of each shaft is the same

15. According to I.B.R., the efficiency of a double riveted butt joint with double cover straps of equal width should be
(A) 45 to 60%
(B) 63 to 70%
(C) 70 to 83%
(D) 80 to 90%

Show and hide multiple DIV using JavaScript View All Answers

Blogger Comment