Engineering Questions with Answers - Multiple Choice Questions
Strength of Materials MCQs Thin Cylinder due to Longitudinal Stress
The longitudinal stress is _____ stress across the section.
Explanation: The tendency of longitudinal stress in a cylinder is to turn away longitudinally. The longitudinal stress is tensile stress across the section.
The longitudinal stress in the shell is _________
Explanation: As longitudinal stress is half the circumferential stress, then f = total pressure/ resisting section.
f = p × π/4 d2 / π d t
f = pd/4t.
The ratio of hoop stress to maximum shear stress is _________
Explanation: Maximum shear stress (q) = (hoop stress – longitudinal stress) / 2
The ratio of hoop stress to maximum shear stress is 4.
At any point on the circumference of the cylinder, the longitudinal and hoop stress are _______
Explanation: At any point on the circumference of the cylindrical shell, the longitudinal (axial stress) and hoop stress(circumferential stress) are always orthogonal to each other.
Calculate the axial stress induced in the pipe is the water mean of 1.5 metres diameter and 20 mm thick is subjected to an internal pressure of 1.5 N/mm2.
a) 28.125 N/mm2
b) 35.675 N/mm2
c) 46.785 N/mm2
d) 67.845 N/mm2
Explanation: Longitudinal stress ( axial stress) = pd / 4t.
f= 1.5 × 1500 / 4 × 20
f= 28.125 N/mm2.
Saprotrophs are also known as _________
a) Detritus Feeders
c) Tertiary consumers
Explanation: Saprotrophs feed on the parts of dead organisms, wales of living organisms and partially decomposed matter. They are also known as the detritivores. Termites, crabs etc. are the examples saprotrophs.
Energy flows through the ecosystem in the form of __________ bonds.
Explanation: Energy flows through the ecosystem in the form of carbon-carbon bonds when respiration occurs, the carbon-carbon bonds are broken and the carbon is combined with oxygen to form carbon dioxide.
Energy does not recycle.
Explanation: Energy is neither created nor destroyed. All energy comes from the sun, and that the ultimate fate of all energy in ecosystem is to be lost as heat. Energy does not recycle.
____________ is a network of food chain of different types of organisms.
a) Food web
b) Food network
c) Food system
d) Food cache
Explanation: Food web is a network of food chains where different types of organisms are connected at different trophic levels. There are the number of options of eating and being eaten at each trophic level.
Ecological pyramids were first devised by __________
a) Earnest Haeckel
b) Roger Federer
c) Charles Eltan
d) Smith Nell
Explanation: An ecological pyramid is a graphic representation of an ecological parameter like a number of individuals. The ecological pyramids were first devised by British ecologist Charles Elton in 1927.
Which of the following is correct?
a) Phytoplankton-zooplanktons- fish
b) Zooplanktons -protozoan-fish
c) Grass- fish- zoo plankton
d) Zooplanktons- phytoplankton-fish
Explanation: The sequence of eating and being eaten in an ecosystem is known as a food chain. Some of the common examples of the simple food chain are grass -grasshopper -frog- snake- hawk (grassland ecosystem).
Phytoplankton-zooplanktons- fish (pond ecosystem).
Wholesome water is also known as _________
a) Palatable water
b) Quality water
c) Lethal water
d) Toxic water
Explanation: Palatable water is the water that it is free from excessive temperature, colour, turbidity taste and odour. It is well aerated. The Wholesome water indicates palatable water.
Rate of demand is also known as __________
a) Domestic demand
b) Per capita demand
c) Commercial demand
d) Livestock demand
Explanation: Rate of demand is the rate of water to be supplied per person per day it is expressed as litres per capita per day.
Per capita demand (or) rate of demand = Q/P×365 litres per day.
Water works are generally design with design period of __________
a) 25 years
b) 30 years
c) 45 years
d) 50 years
Explanation: Water supply projects are designed to serve our specific period of time after completion of the project. This time period is called a design period. The water works are generally designed with a design period of 30 years.
What is a design period for storage dam?
a) 45 years
b) 50 years
c) 60 years
d) 90 years
Answer: b<br />
Explanation: The design period for storage dam is 50 Years.
|Item||Design period (years)|
|Water treatment units||15|
|Raw water and Clear water conveying mains||30|