Engineering Questions with Answers - Multiple Choice Questions
Strength of Materials MCQs Thin Cylinder Under Strain
1 - Question
Calculate the longitudinal strain, if internal pressure is 1.2 N/mm2 and 1 m in diameter along with 10 mm thickness. Take E = 2 × 105N/mm2and Poisson’s ratio as 0.3.
a) 0.00006
b) 0.0006
c) 0.006
d) 0.06
View Answer
Answer: a
Explanation: Longitudinal strain = pd/2tE ×(1/2 – 1/m)
e = 1.2 ×1000 /2×10×2×105×(1/2 – 0.3)
e = 0.00006.
2 - Question
The radial stress in cylinder walls is negligible.
a) True
b) False
View Answer
Answer: a
Explanation: The thickness of the plate is negligible compared to the diameter of shells in a shell is known as thin shell and in the thin shell, the radial stresses are negligible.
3 - Question
bars are also known as __________
a) Transverse bars
b) Radial bars
c) Flexural bars
d) Regant bars
View Answer
Answer: a
Explanation: To resist the cracks due to variation of temperature and shrinkage stresses. The distribution bars are provided in addition to main bars along the shortest span. These bars are also known as transverse bars.
4 - Question
_______ is a saturated bed, which yields water.
a) Aquitard
b) Aquiclude
c) Aquifer
d) Aquifuge
View Answer
Answer: c
Explanation: An aquifer is a saturated bed or geologic formation which yields water in significant quantities. The example for the aquifer is a sand bed.
5 - Question
_______ possesses free surface open to the atmosphere.
a) Aquitard
b) Aquifuge
c) Unconfined aquifer
d) Aquiclude
View Answer
Answer: c
Explanation: An unconfined aquifer is one in which ground water process free open surface to the atmosphere. An aquifuge is an impervious formation that neither contains nor transmits water.
6 - Question
What is the porosity percentage in gravel?
a) 30 – 40 %
b) 50 – 60 %
c) 10 – 20 %
d) 1 – 10 %
View Answer
Answer: a<br />
Explanation: The porosity percentage in gravel is 30 – 40 %.
| Materials | Porosity |
| Clay | 50 -60 % |
| Silt | 40 – 50 % |
| Gravel | 30 – 40 % |
7 - Question
__________ is a measure of its water yielding capacity.
a) Specific capacity
b) Specific weight
c) Specific yield
d) Yield capacity
View Answer
Answer: c
Explanation: The specific yield (Sy) of a material is a measure of its water yielding capacity and it is expressed quantitatively as a percentage of the total volume of material.
8 - Question
_______ is a measure of ease of flow of groundwater.
a) Permeability
b) Porosity
c) Voids ratio
d) Impermeability
View Answer
Answer: a
Explanation: The permeability is a measure of ease of flow of groundwater through aquifers and aquitards and coefficient of permeability is the numbers of litres of water per day that will flow through a medium.
9 - Question
Piezometric surface is a ____________ surface.
a) Real
b) Imaginary
c) Stationary
d) Motive
View Answer
Answer: b
Explanation: Piezometric surface is an imaginary surface to which water rises in wells tapping artesian aquifer.
10 - Question
_________ is a measure of the water retaining capacity of material (rock).
a) Specific capacity
b) Specific yield
c) Specific retention
d) Specific
View Answer
Answer: c
Explanation: Specific retention is denoted by Sr (S suffix r). It is a measure of water retaining capacity.
Sr = Vr/V [Vr = Volume of water retained].
11 - Question
Draw down is also known as __________
a) Frictional head
b) Depression head
c) Tensile head
d) Positive head
View Answer
Answer: b
Explanation: The difference in the level of the original water table and lowered water table due to pumping (or) drawing from a well is called draw down. It is also known as depression head.
12 - Question
The porosity range of sand stone be _________
a) 45 – 55 %
b) 20 – 25 %
c) 10 – 20 %
d) 1 – 10 %
View Answer
Answer: c<br />
Explanation: The porosity range of sand stone be 10 – 20 %.
| Materials | Porosity (%) |
| Gravel | 30 – 40 |
| Gravel and sand | 20 – 25 |
| Sand stone | 10 – 20 |
13 - Question
Recuperation test is carried out to determine yield of well.
a) True
b) False
View Answer
Answer: a
Explanation: Recuperation test K = 2.303 A/T log(H1/H2).
Q = KH
In this test, the water is first lower down to a safe level. The rise of water level and its corresponding time table is noted in a cross-sectional area of well different levels the yield of the well can be calculated.
14 - Question
Calculate thickness of metal, if the pressure inside the water main is 0.6 N/mm2. The diameter of water main is 600 mm. Take hoop stress = 25 N/mm2.
a) 7.20 mm
b) 9.45 mm
c) 10.58 mm
d) 12.24 mm
View Answer
Answer: a
Explanation: Thickness of metal fc = pd/2t
t = pd / 2 fc ;
= 0.6 ×600 / 2 ×25
= 7.2 mm.
15 - Question
Ratio of lateral strain to linear strain is _________
a) Poisson’s ratio
b) Shear strength
c) Shear modulus
d) Bulk modulus
View Answer
Answer: a
Explanation: The ratio of lateral strain to the corresponding longitudinal strain is called poisons ratio and it is denoted by 1 / m.
The value of poisons ratio for elastic materials is in the range of 0.25 to 0.33.