The Higher Technological Institute
(HTI)
Summary type (questions)
Subject:
Submitted by:
Date:
Material lab
From students to students
19/5/2023
Nahla Ahmed Mohamed
Torsion Test
1. What is the unit of polar moment of inertia?
a) m2
b) m5
c) m3
d) m4
2. The shear stress at the outer surface of a solid shaft
with a diameter D and torque T is ……………
𝜋𝑇
a)16𝐷3
16𝐷3
b) 𝜋𝑇
𝜋𝐷3
16𝑇
c) 16𝑇 d)𝜋𝐷3
3. Which of the following is correct assumption made in
the theory of torsion?
a) The twisting couple acts in the transverse plan only.
b) The stress is in plastic zone.
c) The material is perfectly plastic.
d) The material of the shaft is anisotropic.
4. A solid circular shaft of diameter d is subjected to the
twisting moment T. Which of the following relations can be
used to determine the stress developed in the shaft?
16𝑇
a) 𝜏 = 𝜋𝑑3
32𝑇
128𝑇
64𝑇
b)𝜏 = 𝜋𝑑3 c)𝜏 = 𝜋𝑑3 d)𝜏 = 𝜋𝑑3
5. Pure torsion of shaft produces:
a) Longitudinal normal stress in shaft.
b) Only direct shear stress in the transverse section of the
shaft.
c) Circumferential shear stress on a surface element of shaft
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d) A longitudinal shear stress and circumferential shear
stress on a surface element of shaft.
6. Torsional stress multiplied with original cross sectional is:
a) Maximum twisting load b) Minimum twisting load
c) Minimum shear load
d) Yield shear load
7. Which of the following cannot be determined using a
torsion test?
a) Modulus of elasticity in shear b) Torsion yield strength
c) Modulus of rupture
d) Young’s modulus
8. Plastic deformation can only occur in case of torsional
force.
a) True b) False
Explanation: The above given statement is false as plastic
deformation can occur in case of tensile, compressive and torsional
load after a point. After this point, the body cannot recover its
original shape.
9. Shear stress on a solid bar and hollow bar is same for given
dimension.
a) True b) False
Explanation: Shear stress for a hollow bar and a solid bar are
different dimensions as the hollow bar has two dimensions, outer
and inner radius because of which calculation is different than the
solid bar which has only one diameter.
10. In which of the following the angle of twist increases
fast for a small amount of torque?
a) Cold working condition
b) Hot working condition
c) Warm working condition
d) The increase is the same for cold working, hot working and
warm working
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Clarification: When the torsion test is conducted in hot working, it is
observed that for a slight change in torque on the given specimen the
angle of twist increases fast as the material becomes soft at hot
working temperature.
11. Two solid shafts ‘A’ and ‘B’ are made of the same
material. The shaft ‘A’ is of 50 mm diameter and shaft ‘B’ is
of 100 mm diameter. The strength of shaft ‘B’ is ______ of
that of shaft ‘A’.
a) One half. b) double. C)four times.
d) eight times.
𝑇B ⅆB3
=
𝑇A ⅆA3
12. If a constant section beam is subjected to uniform
bending moment throughout, it bends as –
a) Zig zag. b) a catenary c) a circular arc d) a parabolic arc
13. _____________ torsion is produced when twisting
couple coincides with the axis of the shaft.
a) Exact b) Pure c) Nominal d) Mild
14. What are the units of torsional rigidity?
a) Nmm² b) N/mm c) N-mm d) N
15. The angle of twist can be written as ________
a) TL/J b) GJ/TL c) TL/GJ
16.
d) T/J
Torsional sectional modulus is also known as _________
a) Polar modulus
b) Sectional modulus
c) Torsion modulus
d) Torsional rigidity
17.
________ is a measure of the strength of shaft in
rotation.
a) Torsional modulus b) Sectional modulus c) Polar modulus
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d) Torsional rigidity
Explanation: The polar modulus is a measure of the strength of shaft in
rotation. As the value of Polar modulus increases torsional strength
increases.
18. Twisting moment is a product of __________ and the
radius.
a) Direction b) Velocity c)Force d)Acceleration
19.
The shear stress is ____________ at the axis of the shaft.
a) Minimum b) Maximum c) Zero d) Uniform
20. The shear stress at the outer surface of hollow circular
section is _________
a) Zero b) Maximum
c) Minimum d) Can’t determine.
• https://engineeringinterviewquestions.com/mcqs-ontorsional-tests-and-answers/
• https://www.sanfoundry.com/materials-sciencequestions-answers-torsional-tests/
• https://testbook.com/objective-questions/mcq-ontorsion-of-shaft--5eea6a0b39140f30f369deaa
• https://www.sanfoundry.com/strength-materialsquestions-answers-torsion-equation/
• https://epolylearning.com/mcq-questionanswers/Mechanics-of-Materials/Torsion/9
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