5231. The firing order for an in-line four cylinder I.C. engine is
[A]. 1-2-3-4
[B]. 1-3-4-2
[C]. 1-2-4-3
[D]. 1-3-2-4
✅ 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.
5232. The pipe joint mostly used for pipes carrying water at low pressures is
[A]. socket joint
[B]. nipple joint
[C]. union joint
[D]. spigot and socket joint
✅ The correct answer is option A.
5233. During a refrigeration cycle, heat is rejected by the refrigerant in a
[A]. compressor
[B]. condenser
[C]. evaporator
[D]. expansion valve
✅ The correct answer is option B.
5234. In a fuel injection system, the electronic control module (ECM) calculates the optimum fuel-injection volume for the engine condition based on the data received from the sensors, and injects this volume of fuel into the intake manifold at the optimum timing.
[A]. Correct
[B]. Incorrect
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✅ The correct answer is option A.
5235. The ratio of the workdone on the blades to the energy supplied to the blades, is called
[A]. blading efficiency
[B]. nozzle efficiency
[C]. gross or stage efficiency
[D]. mechanical efficiency
✅ The correct answer is option A.
5236. The injection pressure in a diesel engine is about
[A]. 10 bar
[B]. 100 bar
[C]. 150 bar
[D]. 500 bar
✅ The correct answer is option B.
5237. The process of heat transfer from a hot body to a cold body, in a straight line, without affecting the intervening medium, is called radiation.
[A]. True
[B]. False
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null
✅ The correct answer is option A.
5238. If the air-fuel mixture ignites before the spark takes place at spark plug, the condition is called
[A]. detonation
[B]. ignition
[C]. pre-ignition
[D]. rumble
✅ The correct answer is option C.
5239. The increase in pressure in a roots blower is entirely due to back flow of air.
[A]. Agree
[B]. Disagree
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null
✅ The correct answer is option A.
5240. The function of a piston rod is
[A]. to guide motion of the piston rod and to prevent it from bending
[B]. to transfer motion from the piston to the cross head
[C]. to convert heat energy of the steam into mechanical work
[D]. to exhust steam from the cylinder at proper moment
✅ The correct answer is option B.