TORSION SHAFTS MULTIPLE CHOICE QUESTIONS (MCQ) WITH ANSWERS
TORSION SHAFTS
MULTIPLE CHOICE QUESTIONS (MCQ)
WITH ANSWERS
MCQ help in
the design and manufacture of shafts.
Maximum practical failures occur in
shafts because of reversal stresses. Thus
its design requires special attention to
make it really safe under all conditions.
Fig. Torsion of Shafts (a) Shaft is under Torque T, (b) Shaft cross section
_{1. Variation of shear stress in torsion of shaft is}
(a) Parabolic
(b) Linear
(c) Cubical
(d) None
(Ans: b)
Fig. Shear stress Fig. Shear strain variation
variation in a solid shaft in a solid shaft
2. Power in watts in a shaft having N RPM is
(a) Power = 2π NT/60
(b) Power = 2π N T
(c) Power = 2000 π N T/60
(d) None
(Ans: a)
3. Equivalent torque in a shaft subjected to axial load P, torque T and bending moment M is
(a) T_{eq} = (Pa2 + M2 + T2)
(b) T_{eq} = (Pa2 + M2 + T2)^{0.5}
(c)T_{eq} = ( M2 + T2)^{0.5}
(d) None
(Ans: c)
4. Equivalent bending moment in a shaft subjected to axial load P, torque T and bending moment M is
(a) M_{eq} = 0.5 [M + (M2 + T2)0.5]^{0.5}
(b) M_{eq} = 0.5 [M + (M2 + T2)^{0.5}]
(c) M_{eq} = ( M2 + T2)^{0.5}
(d) None
(Ans: b)
5. A power transmitting ductile material shaft under P, T and M will fail under
(a) Tensile considerations only
(b) Compressive considerations only
(c) Shear considerations only
(d) None
(Ans: c)
6. Design a ductile material power transmitting shaft under P, T and M using
(a) Rankine theory
(b) Guest Theory
(c) Haigh theory
(d) None
(Ans: b)
7. From strength point of view, whether hollow or solid power transmitting shaft is preferable
(a) Solid shaft
(b) Hollow shaft
(c) Both solid as well as hollow shaft
(d) None
(Ans: b)
8. The strain energy will be higher in which shaft under the same torque
(a) Solid shaft
(b) Hollow shaft
(c) Same in Solid as well as hollow shaft
(d) None
(Ans: b)
9. Design a shaft for
(a) Strength alone
(b) Stiffness alone
(c) Both for strength and stiffness
(d) None
(Ans: c)
10. Actual stress in the bolts of a flanged coupling of a shaft will be
(a) More than the designed strength
(b) Less than the designed strength
(c) Neither more nor less than the designed strength
(d) None
(Ans: b)
11. Torsion equation is

Firstly T/I =σ/r=Gθ/L

Secondly T/L=τ/r =Gθ/L

Thirdly T/J =τ/y =Gθ/L

None
ANS: (d)
12. Torsion equation is

Firstly T/I =σ/r=Gθ/L

Secondly T/L=τ/r =Gθ/L

Thirdly T/J =τ/r =Gθ/L

None
ANS: (c)

Strain energy in a solid shaft is

Firstly (τ/4G) volume

Secondly (τ^{2}/4G) volume

Thirdly (τ^{3}/4G) volume

None
ANS: (b)

Torsional stiffness of a shaft is

Firstly Gθ

Secondly Gγ

Thirdly GJ

None
ANS: (c )

Maximum number of Loads acting on the shafts is

Torsion & bending

Axial & Torsion

Bending, axial & torsion

None
ANS: (c )

Due to increase of torque, the shaft shear takes place

Parallel to the axis

Perpendicular to the axis

Both parallel & perpendicular to the axis

None
ANS: (b)

The material of the shaft is

Homogeneous and continuous

Isotropic & Homogeneous

Homogeneous, isotropic & continuous

None
ANS: (c )

Distance between two transverse sections is

Variable

Constant

Variable & constant

None
ANS: (b)

Maximum shear stress induced should be less or equal to the

Ultimate limit

Yield limit

Elastic limit

None
ANS: (c )

Polar moment of inertia of a solid shaft is

Firstly (π/64) d^{3}

Secondly (π/32) d^{4}

Thirdly (π/32)d^{3}

None
ANS: (b)
21. Polar moment of inertia of a hollow shaft is

Firstly (π/64) D^{3} –d^{3})

Secondly (π/32) D^{4} –d^{3})

Thirdly (π/32)D^{4} –d^{4})

None
ANS: (c)

Conditions for two shafts connected in series are

Firstly T_{1}=T_{2}=T, &θ_{1} =θ_{2}

Secondly T_{1}+T_{2}=T, &θ_{1} =θ_{2}

Thirdly T_{1}=T_{2}=T, &θ_{1} +θ_{2}=θ

None
ANS: (c )

Conditions for two shafts connected in parallel are
(a) Firstly T_{1}=T_{2}=T, &θ_{1} =θ_{2}
(b) Secondly T_{1}+T_{2}=T, &θ_{1} =θ_{2}
© Thirdly T_{1}=T_{2}=T, &θ_{1} +θ_{2}=θ
(d)None
ANS: (b )
24. Strain energy in a solid shaft is

Firstly τ/4G

Secondly τ^{2}/4G

Thirdly τ^{3}/4G

None
ANS: (d)
25. In torsion of shafts, variation of shear stress is along the

Radius

Length

Both (a) & (b)

None
ANS: (a)
26. Shear stress in a shaft depends on

Torque and radius

Radius & Polar moment of inertia

Radius, torque & polar moment of inertia

None
ANS: ©
27. Polar moment of inertia depends on the

Material of the shaft

Geometry of the shaft

Both (a) & (b)

None
ANS: (b)
28. A force which causes shear stress in a shaft is

Parallel to the area of crosssection

Tangent to the area of crosssection

Both (a) & (b)

None
ANS: (b)
29. In calculating critical speed of a shaft, consider

Lowest frequency

Highest frequency

Both (a) & (b)

None
ANS: (a)
30. Calculate critical speed of a shaft by

RayleighRitz method

Dun Kerley’s method

Both (a) & (b)

None
ANS: (c)
31. Critical speed of a shaft ( RPM) with static deflection ‘y’ is

(g/y)^{5} x 60/π

(g/y _{max})^{5} x 30/π

(g/T)^{5} x 90/π

None
ANS: (b)
32. Critical speed of a shaft depends upon

Amount of unbalance & kind of support

Length & diameter of the shaft

Both (a) & (b)

None
ANS: (c)
33. The reduction in weight of hollow shaft with same outer diameter, length, material.
The inside diameter is half of the outer diameter is

75 %

50 %

25%

None
ANS: (c)
34. Modulus of shear/Young’s modulus of a shaft is

>1

<1

=1

None
ANS: (b)
35. Shafts in series and parallel is like

Resistances in series and parallel

Cells in series and parallel

Both (a) & (b)

None
ANS: (d)
36. A composite shaft consists of

Two materials

Two diameters

Both (a) & (b)

None
ANS: (c)
37. Torque in Shafts in parallel acts at the

Center of shaft

Common radius

Outermost radius

None
ANS: (b)
38. In a shaft with negligible bending moment and axial thrust, principal stresses are

> shear stress

< shear stress

= shear stress

None
ANS: (c)
39. Torsional section modulus of a shaft under torsion is

J/R

R/J

J/D

None
ANS: (a)
40. A shaft of adequate stiffness has a twist of 1^{0} in a length of

10 d

20 d

30 d

None
ANS: (b)
https://mesubjects.net/wpadmin/post.php?post=1155&action=edit Torsion of shafts class notes