Engineering Questions with Answers - Multiple Choice Questions
Strength of Materials MCQs – Stresses in frames – 2
1 - Question
The Velocity at which flow changes from viscous to turbulent is called __________ velocity. a) Critical b) Frictional c) Relative d) Nominal
Answer: a Explanation: A fluid motion is always subjected to a certain resistance. In reality, this resistance is mainly due to sliding. The velocity at which the flow changes from a viscous flow to turbulent flow is called critical velocity.
2 - Question
Flow in circular pipes will be turbulent is Reynolds number is _________ a) 2800 c) = 2800 d) ~ 2800
Answer: b Explanation: Reynold’s number (Re) = Vd/v V = Mean velocity of flow in pipe d = Diameter of pipe v = Kinematic viscosity of liquid Flow in circular pipe will be turbulent if Reynolds number is greater than 2800.
3 - Question
_____ number is the ratio between inertia and viscous forces. a) Lamina’s b) Parker’s c) Macadam’s d) Reynold’s
Answer: d Explanation: Professor Reynold’s deduced from his experiments that at lower velocities the liquid flow was a laminar and at higher velocities, the flow was turbulent. It is a dimensionless number as it is the ratio between inertia and viscous forces.
4 - Question
The frictional resistance is ______ to the surface area of contact. a) Inversely proportional b) Directly proportional c) Equal d) Not equal
Answer: b Explanation: The frictional resistance is directly proportional to the surface area of contact. The frictional resistance is independent of the pressure and where is considerably with temperature.
5 - Question
___________ flow the liquid particles move along straight parallel paths. a) Steady b) Unsteady c) Laminar d) Turbulent
Answer: c Explanation: Flow in circular pipes will be laminar if the Reynolds number is less than 2000. The laminar flow is a type of flow in which the liquid particles move along straight parallel path in layers or laminates.
6 - Question
The __________ resistance is independent of the nature of surface contact. a) Frictional b) Skid c) Shear d) Coupling
Answer: a Explanation: When the liquid flows at a velocity that is less than the critical velocity. A thin stationary film of the liquid is formed on a supporting surface. This is a reason that the frictional resistance is independent of the nature of surface of contact.
7 - Question
Calculate the specific weight of oil. If the specific gravity is 0.95. Take specific weight of water is 1000 kg/m3. a) 750 kg/m3 b) 850 kg/m3 c) 950 kg/m3 d) 1250 kg/m3
Answer: c Explanation: The specific gravity (S) = specific weight of oil / specific weight of Specific weight of oil = S × specific weight of water Specific weight of oil = 0.95 × 1000 = 950 kg/m3.
8 - Question
In _______ liquid flows under atmospheric pressure. a) Pipe flow b) Open channel c) Stream d) Aqueduct
Answer: b Explanation: Liquid flows under atmospheric pressure in an open channel due to its slope of the channel. There must be some slope in the bed of the channel to flow to take place.
9 - Question
The energy gradient line is _______ to drop in bed, in an open channel. a) Equal b) Parallel c) Perpendicular d) Unequal
Answer: a Explanation: For uniform flow in an open channel the drop in the energy gradient line is equal to drop in bed. Flows in irrigation channels, streams and rivers are some examples of open channel flow.
10 - Question
Aqueduct is an example of __________ channel. a) Natural b) Prismatic c) Non prismatic d) Artificial
Answer: d Explanation: An artificial channel is the one which is built artificially for some specific purpose such as irrigation water supply and water power development etc. The examples include canals, drainage gutters and aqueducts.
11 - Question
Rectangular channel is _________ channel. a) non Prismatic b) Prismatic c) Natural d) Artificial
Answer: b Explanation: A channel is said to be prismatic if the cross-section is uniform and the bed slope is constant throughout its length. The rectangular channel comes under Prismatic channel.
12 - Question
Expand RVF _________ a) Rapid Vary Fluid b) Rise in Virtual Flow c) Rapidly Varied flow d) Rapidly Viscous flow
Answer: c Explanation: RVF stands for Rapidly Varied Flow. If the depth floor changes abruptly over a comparatively shorter distance, the flow is characterised as rapidly varied flow. Typical examples of rapidly varied flow are hydraulic jump and hydraulic drop.
13 - Question
Froude number is the ratio of inertial force to the _________ force. a) Shear b) Gravity c) Uplift d) Viscous
Answer: b Explanation: The ratio of the inertia force and gravity force is known as the Froude number. It is denoted by Fr. Fr = V/(gD)1/2.
14 - Question
For super critical flow, Fr _________ 1. a) > b) < c) = d) ~
Answer: a Explanation: Froude number the ratio of inertial force to the gravity force. Fr = V/(gD) 1/2 For supercritical flow, Fr > 1.
15 - Question
Strut is a tension member. a) True b) False
Answer: b Explanation: Strut is the member of a structure any position carrying the compressive load. It may be horizontal, inclined or even vertical.