MCQOPTIONS
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MCQOPTIONS
This section includes 482 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 101. |
When a steel containing less than 0.8% carbon is cooled slowly from temperatures above or within the critical range, it consists of |
| A. | mainly ferrite |
| B. | mainly pearlite |
| C. | ferrite and pearlite |
| D. | pearlite and cementite |
| Answer» D. pearlite and cementite | |
| 102. |
Eutectoid reaction occurs at |
| A. | 600°C |
| B. | 723°C |
| C. | 1147°C |
| D. | 1493°C |
| Answer» C. 1147°C | |
| 103. |
The material widely used for making pendulums of clocks is |
| A. | stainless steel |
| B. | high speed steel |
| C. | heat resisting steel |
| D. | nickel steel |
| Answer» E. | |
| 104. |
In induction hardening __________ is high. |
| A. | current |
| B. | voltage |
| C. | frequency |
| D. | temperature |
| Answer» D. temperature | |
| 105. |
The metal suitable for bearings subjected to light loads, is |
| A. | silicon bronze |
| B. | white metal |
| C. | monel metal |
| D. | phosphor bronze |
| Answer» E. | |
| 106. |
The addition of copper to aluminium possesses maximum strength after heat treatment and age-hardening |
| A. | Correct |
| B. | Incorrect |
| Answer» B. Incorrect | |
| 107. |
Nickel when added to copper improves |
| A. | machinability |
| B. | hardness |
| C. | hardness and strength |
| D. | strength and ductility |
| Answer» C. hardness and strength | |
| 108. |
The machinability of aluminium increases when __________ is added to aluminium. |
| A. | copper |
| B. | magnesium |
| C. | silicon |
| D. | lead and bismuth |
| Answer» E. | |
| 109. |
Body centred cubic space lattice is found in |
| A. | zinc, magnesinm, cobalt, cadmium, antimony and bismuth |
| B. | gamma-iron, aluminium, copper, lead, silver and nickel |
| C. | alpha-iron, tungsten, chromium and molybdenum |
| D. | none of the above |
| Answer» D. none of the above | |
| 110. |
Which of the following impurity in cast iron promotes graphite nodule formation and increases the fluidity of the molten metal? |
| A. | Silicon |
| B. | Sulphur |
| C. | Manganese |
| D. | Phosphorus |
| Answer» B. Sulphur | |
| 111. |
An aluminium alloy with 11% silicon is used for making engine pistons by die casting technique. |
| A. | Yes |
| B. | No |
| Answer» B. No | |
| 112. |
The carbon in the pig iron varies from |
| A. | 0.1 to 0.5% |
| B. | 0.5 to 1% |
| C. | 1 to 5% |
| D. | 5 to 10% |
| Answer» D. 5 to 10% | |
| 113. |
The type of space lattice found in alpha-iron is |
| A. | face centred cubic space lattice |
| B. | body centred cubic space lattice |
| C. | close packed hexagonal space lattice |
| D. | none of these |
| Answer» C. close packed hexagonal space lattice | |
| 114. |
When a low carbon steel is heated upto lower critical temperature, |
| A. | there is no change in grain size |
| B. | the average grain size is a minimum |
| C. | the grain size increases very rapidly |
| D. | the grain size first increases and then decreases very rapidly |
| Answer» B. the average grain size is a minimum | |
| 115. |
Grey cast iron is __________ than white cast iron. |
| A. | softer |
| B. | harder |
| Answer» B. harder | |
| 116. |
Corrosion resistance of steel is increased by adding nickel and chromium. |
| A. | Agree |
| B. | Disagree |
| Answer» B. Disagree | |
| 117. |
Ball bearings are, usually, made from |
| A. | low carbon steel |
| B. | high carbon steel |
| C. | medium carbon steel |
| D. | chrome steel |
| Answer» E. | |
| 118. |
Hindalium is an alloy of aluminium and magnesium with a small quantity of chromium. |
| A. | Agree |
| B. | Disagree |
| Answer» B. Disagree | |
| 119. |
The ratio of the volume occupied by the atoms to the total volume of the unit cell is called |
| A. | coordination number |
| B. | atomic packing factor |
| C. | space lattice |
| D. | none of these |
| Answer» C. space lattice | |
| 120. |
The property of a material which enables it to retain the deformation permanently, is called |
| A. | brittleness |
| B. | ductility |
| C. | malleability |
| D. | plasticity |
| Answer» E. | |
| 121. |
The brown smoke during the operation of a bessemer Converter indicates that the |
| A. | air is burning out silicon and managanese |
| B. | silicon and manganese has burnt and carbon has started oxidising |
| C. | the converter must be titled to remove the contents of the converter |
| D. | the brown smoke does not occur during the operation of a bessemer converter |
| Answer» B. silicon and manganese has burnt and carbon has started oxidising | |
| 122. |
Martensite has needle like structure and is magnetic. |
| A. | Correct |
| B. | Incorrect |
| Answer» B. Incorrect | |
| 123. |
In induction hardening, the depth of hardening is controlled by controlling the voltage. |
| A. | Correct |
| B. | Incorrect |
| Answer» B. Incorrect | |
| 124. |
The austenite is a solid solution of carbon or iron carbide in gamma-iron. |
| A. | Correct |
| B. | Incorrect |
| Answer» B. Incorrect | |
| 125. |
Sulphur in cast iron |
| A. | makes the iron soft and easily machinable |
| B. | increases hardness and brittleness |
| C. | makes the iron white and hard |
| D. | aids fusibility and fluidity |
| Answer» C. makes the iron white and hard | |
| 126. |
Cementite consist of |
| A. | 13% carbon and 87% ferrite |
| B. | 13% cementite and 87% ferrite |
| C. | 13% ferrite and 87% cementite |
| D. | 6.67% carbon and 93.33% iron |
| Answer» E. | |
| 127. |
When a low carbon steel is heated upto upper critical temperature |
| A. | there is no change in grain size |
| B. | the average grain size is a minimum |
| C. | the grain size increases very rapidly |
| D. | the grain size first increases and then decreases very rapidly |
| Answer» C. the grain size increases very rapidly | |
| 128. |
Combined carbon in iron makes the metal |
| A. | soft and gives coarse grained crystalline structure |
| B. | soft and gives a fine grained crystalline structure |
| C. | hard and gives a coarse grained crystalline structure |
| D. | hard and gives a fine grained crystalline structure |
| Answer» E. | |
| 129. |
Cast iron is a ductile material. |
| A. | Correct |
| B. | Incorrect |
| Answer» C. | |
| 130. |
Manganese is added in low carbon steel to |
| A. | make the steel tougher and harder |
| B. | raise the yield point |
| C. | make the steel ductile and of good bending qualities |
| D. | all of the above |
| Answer» D. all of the above | |
| 131. |
Beryllium bronze contains |
| A. | 60% copper and 40% beryllium |
| B. | 80% copper and 20% beryllium |
| C. | 97.75% copper and 2.25% beryllium |
| D. | 99% copper and 1% beryllium |
| Answer» D. 99% copper and 1% beryllium | |
| 132. |
Gamma-iron occurs between the temperature range of |
| A. | 400°C to 600°C |
| B. | 600°C to 900°C |
| C. | 900°C to 1400°C |
| D. | 1400°C to 1530°C |
| Answer» D. 1400°C to 1530°C | |
| 133. |
Incoloy, Hastelloy and Vitallium are __________ temperature alloys. |
| A. | high |
| B. | low |
| Answer» B. low | |
| 134. |
Quenching is not necessary when hardening is done by |
| A. | case hardening |
| B. | flame hardening |
| C. | nitriding |
| D. | any one of these |
| Answer» D. any one of these | |
| 135. |
The iron ore in the charge of blast furnace acts as an iron bearing mineral. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 136. |
Beryllium bronze has |
| A. | high yield point |
| B. | high fatigue limit |
| C. | both (a) and (b) |
| D. | none of these |
| Answer» D. none of these | |
| 137. |
When filing or machining cast iron makes our hands black, then it shows that __________ is present in cast iron. |
| A. | cementite |
| B. | free graphite |
| Answer» C. | |
| 138. |
According to Indian standard specifications, a plain carbon steel designated by 40 C8 means that the carbon content is |
| A. | 0.04% |
| B. | 0.35 to 0.45% |
| C. | 0.4 to 0.6% |
| D. | 0.6 to 0.8% |
| Answer» C. 0.4 to 0.6% | |
| 139. |
In iron, the presence of carbon in free form is called graphite. |
| A. | Agree |
| B. | Disagree |
| Answer» B. Disagree | |
| 140. |
In a body centred cubic space lattice, there are nine atoms out of which eight atoms are located at the corners of the cube and one atom at its centre. |
| A. | Yes |
| B. | No |
| Answer» B. No | |
| 141. |
There are fourteen atoms in a unit cell of |
| A. | body centred cubic space lattice |
| B. | face centred cubic space lattice |
| C. | close packed hexagonal space lattice |
| D. | none of these |
| Answer» C. close packed hexagonal space lattice | |
| 142. |
The maximum internal diameter of a blast furnace is about |
| A. | 3 m |
| B. | 6 m |
| C. | 9 m |
| D. | 12 m |
| Answer» D. 12 m | |
| 143. |
In spheroidising process, the steel is |
| A. | heated below the lower critical temperature and then cooled slowly |
| B. | heated upto the lower critical temperature and then cooled in still air |
| C. | heated slightly above the lower critical temperature and then cooled slowly to a temperature of 600°C |
| D. | none of the above |
| Answer» D. none of the above | |
| 144. |
Pearlite is a combination of 87% ferrite and 13% cementite. |
| A. | Yes |
| B. | No |
| Answer» B. No | |
| 145. |
The percentage carbon content in wrought iron is about |
| A. | 0.02 |
| B. | 0.1 |
| C. | 02 |
| D. | 0.4 |
| Answer» B. 0.1 | |
| 146. |
Spheroidal grey cast iron has graphite flakes. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 147. |
Chromium when added to steel __________ the tensile strength. |
| A. | does not effect |
| B. | decreases |
| C. | increases |
| Answer» D. | |
| 148. |
Which of the following is added in low carbon steels to prevent them from becoming porous? |
| A. | Sulphur |
| B. | Phosphorus |
| C. | Manganese |
| D. | Silicon |
| Answer» E. | |
| 149. |
A steel with carbon __________ is known as hypo-eutectoid steel. |
| A. | 0.8% |
| B. | below 0.8% |
| C. | above 0.8% |
| Answer» C. above 0.8% | |
| 150. |
Which of the following when used in ordinary low carbon steels, makes the metal ductile and of good bending qualities? |
| A. | Sulphur |
| B. | Phosphorus |
| C. | Manganese |
| D. | Silicon |
| Answer» D. Silicon | |