# Design of Machine Elements 12

Mechanical Engineering MCQ Question Papers: DRDO, ISRO, Interview

Subject: Design of Machine Elements 12

Part 6: List for questions and answers of Design of Machine Elements –II

Q1.A sliding bearing which can support steady loads without any relative motion between the journal and the bearing, is called
a) Zero film bearing
b) Boundary lubricated bearing
c) Hydrodynamic lubricated bearing
d) Hydrostatic lubricated bearing

Q2.A machine part subjected to…………..is called a strut
a) An axial tensile force
b) An axial compressive force
c) A tangential force
d) Any one of these

Q3.When two helical springs of equal lengths are arranged to form a cluster spring, then
a) Shear stress in each spring will be equal
b) Load taken by each spring will be half the total load
c) All of the above
d) None of these

Q4.The dedendum circle diameter is equal to (where φ = Pressure angle)
a) Pitch circle diameter x cos φ
b) Addendum circle diameter x cos φ
c) Clearance circle diameter x cos φ
d) Pitch circle diameter x sin φ

Q5.Which one of the following is a positive drive?
a) Crossed flat belt drive
b) Rope drive
c) V-belt drive
d) Chain drive

Q6.The included angle for the British Association thread is
a) 29°
b) 47.3°
c) 55°
d) 60°

Q7.The contact ratio is the ratio of
a) Length of path of contact to the circular pitch
b) Length of arc of contact to the circular pitch
c) Length of arc of approach to the circular pitch
d) Length of arc of recess to the circular pitch

Q8.When the speed of belt increases,
a) The coefficient of friction between the belt and pulley increases
b) The coefficient of friction between the belt and pulley decreases
c) The power transmitted will decrease
d) The power transmitted will increase

Q9. An involutes pinion and gear are in mesh. If both have the same size of addendum, then there will be interference between the
a) Tip of the gear and flank of pinion
b) Tip of the pinion and flank of gear
c) Flanks of both gear and pinion
d) Tip of both gear and pinion

Q10.The helix angle for single helical gears ranges from
a) 10° to 15°
b) 15° to 20°
c) 20° to 35°
d) 35° to 50°

Q11.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

Q12.The design of pin of a rocker arm of an I.C. engine is based on
a) Bearing failure
b) Shearing failure
c) Bending failure
d) All of these

Q13.Lewis equation in gears is used to find the
a) Tensile stress in bending
b) Shear stress
c) Compressive stress in bending
d) Fatigue stress

Q14.In order to determine the stresses in a thin cylinder due to an internal pressure, it is assumed that
a) The effect of curvature of the cylinder wall is neglected
b) The tensile stresses are uniformly distributed over the section of the walls
c) The effect of the restraining action of the heads at the end of the pressure vessel is neglected
d) All of the above

Q15.All stresses produced in a belt are
a) Compressive stresses
b) Tensile stresses
c) Both tensile and compressive stresses
d) Shear stresses

Q16.An elastic bar is fixed at the upper end and loaded at the lower end by a falling weight. The shock load produced can be reduced by
a) Increasing the length of bar
b) Decreasing the cross-sectional area of the bar
c) Decreasing the modulus of elasticity of the bar
d) All of the above

Q17.The ratio of driving tensions in V-belt drives is __________ flat belt drives
a) Equal to
b) Sin α ± times more than
c) Sin α ± times less than
d) Cosec α ± times more than

Q18.Which of the following spring is used in mechanical wrist watch?
a) Helical compression spring
b) Spiral spring
c) Torsion spring
d) Bellevile spring

Q19.A pressure vessel is said to be a thick shell, if the ratio of wall thickness to its diameter is
a) Equal to 1/10
b) Less than 1/10
c) Greater than 1/10
d) None of these

Q120.The resilience of a bolt may be increased by
a) Increasing its shank diameter
b) Increasing its length
c) Decreasing its shank diameter
d) Decreasing its length

Part 6: List for questions and answers of Design of Machine Elements –II