⚙️ Mechanical Eng Solved MCQs with Answers

Practice 934 approved ⚙️ Mechanical Eng questions with verified answers from the 🛠️ Engineering Essentials subject for Pakistan exams.

934 solved MCQs

The nuclear power station at Tarapur has the reactor of the __________ type.Answer: boiling water Silicon when added to copper improvesAnswer: hardness and strength In nuclear power plants, due to reflector, less fuel is needed to generate sufficient neutrons to sustain a chain reaction.Answer: Yes The alloying element which increases residual magnetism and coercive magnetic force in steel for magnets isAnswer: cobalt Cast iron is manufactured inAnswer: cupola The lower critical point for all steels isAnswer: 723°C The secondary fuel used in nuclear power plants isAnswer: U₂₃₃ and Pu₂₃₉ Haematite iron ore contains iron aboutAnswer: 70% The material in which the atoms are arranged regularly in some directions but not in others, is calledAnswer: mesomorphous material The steel produced by bessemer or open hearth process is __________ to that produced by L-D process.Answer: inferior Crystal structure of a material is, generally, examined byAnswer: X-ray techniques Iron-carbon alloys containing 1.7 to 4.3% carbon are known asAnswer: hypo-eutectic cast irons The coke in the charge of blast furnaceAnswer: supplies heat to reduce ore and melt the iron Nimonic contains __________ percentage of nickel as that of Inconel.Answer: same The heat treatment process used for softening hardened steel isAnswer: tempering The dieing down of a white flame during the operation of a bessemer converter indicates that the air is burning out silicon and manganese.Answer: No The electric process of steel making is especially adopted toAnswer: all of these Iron ore is, usually, found in the form ofAnswer: all of these The hardness of steel increases if it containsAnswer: cementite In full annealing, the hypo-eutectoid steel is heated from 30° C to 50° C above the upper critical temperature and then cooledAnswer: slowly in the furnace Ferrite and pearlite makes the steel soft and ductile.Answer: Agree The lower critical temperatureAnswer: is same for all steels Nodular cast iron is produced by adding __________ to the molten cast iron.Answer: magnesium Free carbon in iron makes the metalAnswer: soft and gives a coarse grained crystalline structure The cupola is used to manufactureAnswer: cast iron The type of space lattice found in gamma-iron isAnswer: face centred cubic space lattice The property of a material due to which it breaks with little permanent distortion, is calledAnswer: brittleness In which of the following the electrically energy is converted into mechanical energy?Answer: Washing machine Which of the following materials is not used for expansion purposes?Answer: Wood The angle at which X and Y components of a force are equal is?Answer: 45°