This set of Strength of Materials MCQs focuses on “Thin Cylinder due to Longitudinal Stress on Surface of Cylinder”.
1. Calculate the hoop stress at the bottom of penstock, if a steel penstock of 1 m and 10 mm thick is subjected to 100m head of water. Take w = 9.81 kN/m3.
a) 49 N/mm2
b) 47 N/mm2
c) 45 N/mm2
d) 43 N/mm2
Explanation: We know that p = wh ; p = 9.81×100 = 981 kN/m2= 0.981 N/mm2.
Hoop stress = pd/2t = 0.981 ×1000/2×10 = 49 N/mm2.
2. Maximum daily demand = _____ × Average daily demand.
Explanation: Peak demand is a maximum consumption of water in an hour or in a day the effects of monthly variations of flow influences the design of pumps and services reservoirs.
Maximum daily demand = 1.5 × Average daily demand.
3. Which of the following is not a short term estimate in population forecast?
a) Graphical comparison
b) Geometrical increase method
c) Arithmetical increase method
d) Graphical extension method
Explanation: Graphical comparison is a long term estimate. In this estimate, the population time curve of a given community can be extrapolated on the basis of trends experienced by similar and larger communities.
4. Pn = P[1+r/100]n is a formula used in ___________
a) Arithmetical increase method
b) Incremental increase method
c) Geometrical increase method
d) Graphical extension method
Explanation: Geometrical increase method is used for young and rapidly growing cities
The formula used is Pn = P[1+r/100]n; Where Pn = population of “n” decades
r = percentage rate of increase per year
n = number of years or decades.
5. According to Freeman, estimate of fire demand can be made from the formula?
a) Q = 3175 P
b) Q = 2125 P
c) Q = 1136.5 (P/5 +10)
d) Q = 2715 (P/5 + 10)
Explanation: Fire fighting demand is provided acquisition draught on distribution system with normal supply to the consumers according to J R freeman’s formulae :
Q = 1136.5 ( P/5 + 10 )
Q = quantity of water in litres per minute
P = population in thousands.
6. Fire hydrants are located in a main at a distance of ______________
a) 200 to 250 m
b) 150 to 200 m
c) 100 to 150 m
d) 50 to 100 m
Explanation: A sufficient amount of water must therefore always be available to satisfy the peak demand and extinguish any possible fire. For effective fire protection, hydrants are located at about 150 m intervals.
7. In total consumption, losses account about __________
Explanation: In total consumption, losses account about 15 %.
|Types of consumption||Percentage varies|
|Industrial and commercial demand||25 %|
|Public demand||15 %|
8. _______ is integrated or summation hydrograph.
a) Mass curve
b) Mild curve
c) Ryve’s curve
d) Dicken’s curve
Explanation: Mass curve diagram is the integrated or summation hydrograph. It shows the relation between time and cumulative discharges in a river.
9. ___________ is an example of a subsurface source.
b) Impounding reservoir
Explanation: When ground water appears at the surface for any reason springs are formed. The springs generally can supply small quantity of water.
10. Infiltration wells are ____________ wells constructed in series.
Explanation: Infiltration wells are the vertical shallow wells constructed in series along the banks of rivers. The wells are connected by Porous pipes to a sump well called “jack well”.
11. _______ are the horizontal tunnels laid along the banks of river.
a) Infiltration wells
b) infiltration reservoir
c) infiltration galleries
d) infiltration Springs
Explanation: Infiltration galleries are used as source of water supply. These are the horizontal tunnels which are constructed through water bearing strata. They are usually laid along the banks of rivers, so that water can be drawn across the line of flow.
12. Carbonic acid is high in ______ springs.
Explanation: Surface springs are formed when subsoil water is exposed to the ground. The spring water which is not disturbed by the rainfall is usually attractive in appearance and of good palatability. However, the content of free carbonic acid is sometimes high and spring water may possess corrosive and plumb solvent properties.
13. In _________ springs, that trench acts as a storage reservoir.
Explanation: Gravity springs are developed due to overflowing of water table. The flow from a gravity spring is variable with rise or fall of water table. In order to meet with such fluctuations, a trench may be constructed near such spring. That trench acts as a storage reservoir.
14. Which of the following wells are also known as water table well?
a) Deep wells
b) Open wells
c) Shallow wells
d) Sunk wells
Explanation: Shallow well is a well which supply from the uppermost aquifer. The flow into the wells takes place only by gravity. Due to this depression, the well is also known as gravity well or water table well.
15. Calculate the strain energy of a member bearing stress of 0.0366 N/mm2. If the length of the member is 1 m and a cross section area is 60000mm2. Take E = 2 × 105 N/mm2.
a) 0.4 Nmm
b) 0.5 Nmm
c) 0.6 Nmm
d) 0.2 Nmm
Explanation: Strain energy = f2/ 2E × Volume
= (0.0366)2 / 2 × 2 × 105 × ( 60000) × 1000
= 0.2 Nmm.
Sanfoundry Global Education & Learning Series – Strength of Materials.
To practice MCQs on all areas of Strength of Materials, here is complete set of 1000+ Multiple Choice Questions and Answers.