5281. When the speed of the crankshaft is between 100 r.p.m. and 250 r.p.m., the engine said to be a
[A]. slow speed engine
[B]. medium speed steam engine
[C]. high speed steam engine
[D]. none of these
✅ The correct answer is option B.
Mechanical Engineering
Prepare with the best Mechanical Engineering MCQs with answers and explanations for exams, interviews, and job tests. Our collection covers core topics such as engineering mechanics, thermodynamics, strength of materials, theory of machines, fluid mechanics, heat transfer, manufacturing processes, machine design, and power plant engineering. These Mechanical Engineering multiple-choice questions are designed for students, fresh graduates, and professionals preparing for NTS, PPSC, FPSC, PEC exams, GATE, university entry tests, and recruitment assessments. Strengthen your technical knowledge and problem-solving ability with our updated and comprehensive Mechanical Engineering MCQs.
5282. Steam turbines are used for
[A]. large marine propulsion
[B]. electric power generation
[C]. direct drive of fans, compressors, pumps
[D]. all of these
✅ The correct answer is option D.
5283. Which of the following has the minimum atomic mass?
[A]. Oxygen
[B]. Sulphur
[C]. Nitrogen
[D]. Carbon
✅ The correct answer is option D.
5284. A left hand tool on a lathe cuts most efficiently when it travels
[A]. from left to right end of the lathe bed
[B]. from right to left end of the lathe bed
[C]. with the help of a compound slide
[D]. across the bed
✅ The correct answer is option A.
5285. Reynolds number (RN) is given by (where h = Film coefficient, l = Linear dimension, V = Velocity of fluid, k = Thermal conductivity, t = Temperature, ρ = Density of fluid, cp = Specific heat at constant pressure, and μ = Coefficient of absolute viscosity)
[A].
[B].
[C].
[D].
✅ The correct answer is option C.
5286. The coke in the charge of blast furnace
[A]. controls the grade of pig iron
[B]. acts as an iron-bearing mineral
[C]. supplies heat to reduce ore and melt the iron
[D]. forms a slag by combining with impurities
✅ The correct answer is option C.
5287. Degree of saturation or percentage humidity is
[A]. the mass of water vapour present in 1 m3 of dry air
[B]. the mass of water vapour present in 1 kg of dry air
[C]. the ratio of the actual mass of water vapour in a unit mass of dry air to the mass of water vapour in the same mass of dry air when it is saturated at the same temperature and pressure.
[D]. the ratio of actual mass of water vapour in a given volume of moist air to the mass of water vapour in the same volume of saturated air at the same temperature and pressure
✅ The correct answer is option C.
5288. The capacity of a hydraulic accumulator is generally specified as the maximum amount of energy stored.
[A]. True
[B]. False
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✅ The correct answer is option A.
5289. The thermal efficiency of diesel engines is about
[A]. 15%
[B]. 30%
[C]. 50%
[D]. 70%
✅ The correct answer is option D.
5290. When the connection between the two elements is such that only required kind of relative motion occurs, it is known as self-closed pair.
[A]. Right
[B]. Wrong
null
null
✅ The correct answer is option A.