WorksheetsTheory Quiz (DPN20123) - Chapter 8
Total questions: 20
Worksheet time: 55mins
Torsional sectional modulus is also known as _________
Polar modulus
Sectional modulus
Torsion modulus
Torsional rigidity
What are the units of torsional rigidity?
Nmm^2
N/mm
N-mm
N
A shaft is said to be in pure torsion if
Turning moment is applied at one end and other end is free
Turning force is applied at one end and other end is free
Two opposite turning moments are applied to the shaft
Combination of torsional load and bending load is applied to the shaft
Which material is suitable for shaft material?
High speed steel
Stainless steel or high carbon steel
Grey cast iron
Steel having approx. 0.4% carbon and 0.8% manganese
Two shafts in torsion will have equal strength if
Only diameter of the shafts is same
Only angle of twist of the shaft is same
Only material of the shaft is same
Only torque transmitting capacity of the shaft is same
Which of the following is incorrect?
In torsion equation, we use mean torque
In torsion equation, we use maximum torque
Many shafts are designed under combined bending and torsion load
Shafts are also designed for torsional rigidity
Which of the following is incorrect?
In a solid shaft maximum shear stress occurs at radius = radius of shaft
In a solid shaft maximum shear stress occurs at center
In a hollow shaft maximum shear stress occurs at outer radius
In a hollow shaft minimum shear stress occurs at inner radius
Which of the following is not an assumption in derivation of torsion equation?
Circular shaft remains circular after twisting
Plane section of the shaft remain plane after twisting
Material of shaft is isotropic
Angle of twist is proportional to radius
Strength of a shaft
Is equal to maximum shear stress in the shaft at the time of elastic failure
Is equal to maximum shear stress in the shaft at the time of rupture
Is equal to torsional rigidity
Is ability to resist maximum twisting moment
For same weight, same material, same length
Solid shaft is always stronger than a hollow shaft
Solid shaft is always weaker than a hollow shaft and strength ratio will depend upon Do/Di of hollow shaft
Strength of both the shafts in equal
Strength of a solid shaft is always weaker and the strength ratio will depend upon Do/Di of hollow shaft
For two shafts in series or having different diameters for two parts of length
T = T1 + T2
T = T1 = T2
T = T1 – T2
T = (T1.T2)^1/2
For two shafts in parallel or for two concentric shafts
T = T1 + T2
T = T1 = T2
T = T1 – T2
T = (T1.T2)^1/2
Which of the following assumptions are made in torsion theory?
Shaft is perfectly straight
Material of the shaft is heterogeneous
Twist cannot be uniform along the length of the shaft
All of the above
A member subjected to couple produces rotational motion about its longitudinal axis called as ________
torsion
twisting moment
both a. and b.
none of the above
Stress in the cross section of a shaft at the centre ________
is zero
decreases linearly to the maximum value of at outer surface
both a. and b.
none of the above
The safe twisting moment for a compound shaft is equal to the
Maximum calculated value
Minimum calculated value
Mean value
Extreme value
The torsional rigidity of a shaft is expressed by the
Maximum torque it can transmit
Number of cycles it undergoes before failure
Elastic limit upto which it resists torsion, shear and bending stresses torque required to produce a twist of one radian per unit length of shaft
maximum power it can transmit at highest possible speed.
A shaft is said to be in pure torsion if
Turning moment is applied at one end and other end is free
Turning force is applied at one end and other end is free
Two opposite turning moments are applied to the shaft
Which property is not required for shaft materials?
High shear and tensile strength
Good castability
High fatigue strength
Which material is suitable for shaft material?
Stainless steel or high carbon steel
Grey cast iron
Steel having approx. 0.4% carbon and 0.8% manganese
All of the above
