Torsion-Short notes, Derivation, and Example problems

1. CE8395
STRENGTH OF MATERIALS FOR
MECHANICAL ENGINEERS
By,
Dr.S.SURESH,
Assistant Professor,
Department of Mechanical Engineering
UNIT-III
TORSION
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2. TORQUE
• Torque is a measure of the force that can cause an
object to rotate about an axis.
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3. TORSION
•Twisting of an object due to an applied torque.
•Expressed in newton metres (N.m)
•This cause shear stress in the material of the shaft.
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9. TORSIONAL RIGIDITY
 Torsional rigidity or stiffness of the shaft is defined as
the product of shear modulus and polar moment of
inertia.
 Torque required to produce a twist of one radian per
unit length of the shaft.
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21. TORSIONAL SECTION MODULUS (OR) POLAR MODULUS
 Polar modulus is defined as the ratio of
the polar moment of inertia to the radius of the shaft.
It is also called as torsional section modulus. It is
denoted by Z p.
Application:
Polar Modulus (Z) is a Direct Measure of Torsional strength of a Shaft
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34. SUMMARY
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