Top 50 Mechanical Engineering MCQ Questions and Answers Pdf

Top 50 Mechanical Engineering MCQ Questions and Answers Pdf

Mar 21, 2024, By Meritnotes

Question 1 :

Diesel locomotives in India are manufactured at

(a) Varanasi

(b) Chitranjan

(c) Parambur

(d) Bangalore

Answer: A

Varanasi

Question 2 :

A ship is powered by

(a) Steam turbines, diesel engines or hydraulic turbines

(b) Steam turbines or diesel engines

(c) Diesel engines

(d) Steam turbine

Answer: B

Steam turbines or diesel engines

Question 3 :

Which of the following place is associated with thermal power plants?

(a) Agra

(b) Delhi

(c) Panipat

(d) Bhakra

Answer: C

Panipat

Question 4 :

Heavy water production plants in India are located at all the following places except

(a) Tuticorin

(b) Baroda

(c) Mumbai

(d) Nangal

Answer: C

Mumbai

Question 5 :

Grashoff number has significant role in heat transfer by

(a) Conduction

(b) Radiation

(c) Forced convection

(d) Natural convection

Answer: D

Natural convection

Question 6 :

Which of the following material has the best thermal conductivity?

(a) Aluminium

(b) Cadmium copper

(c) Galvanised steel

(d) Copper

Answer: D

Copper

Question 7 :

Earth coal is

(a) Wet coal

(b) Black earth

(c) Coal dust

(d) Lignite

Answer: D

Lignite

Question 8 :

A jet aircraft is powered by

(a) Batteries

(b) Gas turbine

(c) Diesel engines

(d) Petrol engines

Answer: B

Gas turbine

Question 9 :

Which of the following gives nearly monochromatic light?

(a) Mercury vapour lamp

(b) Fluorescent tube

(c) GLS lamp

(d) Sodium vapour lamp

Answer: D

Sodium vapour lamp

Question 10 :

In die casting

(a) The heat loss from molten metal is fast as the mould is metallic

(b) There is no restriction of material, any material that can be poured can be cast

(c) There is no need of air venting

(d) The product surface is smooth and clean without the parting line

Answer: A

The heat loss from molten metal is fast as the mould is metallic

Question 11 :

Ablation heat transfer method is used on

(a) Nuclear war heads

(b) Satellites

(c) Rockets

(d) Submarines

Answer: B

Satellites

Question 12 :

In steam power plants, exhaust steam from turbine goes to

(a) Air preheater

(b) Condenser

(c) Cooling tower

(d) Economiser

Answer: B

Condenser

Question 13 :

Which method can be used for heating wood?

(a) Dielectric heating

(b) Radiation heating

(c) Resistance heating

(d) Flame heating

Answer: A

Dielectric heating

Question 14 :

Metals are good conductors of heat because

(a) They have reflecting surfaces

(b) Their atoms collide frequently

(c) Their atoms are relatively far apart

(d) They contain free electrons

Answer: D

They contain free electrons

Question 15 :

Cold heating is a process of

(a) Electro-machining process

(b) Pneumatic mechanical forming

(c) Explosives forming

(d) High energy rate forming

Answer: A

Electro-machining process

Question 16 :

Cutting speed in turning operations is maximum in case of

(a) Aluminium

(b) Brass

(c) Cast iron

(d) Mild steel

Answer: A

Aluminium

Question 17 :

Which one of the following methods is generally not used in welding of chromium molybdenum steels

(a) Resistance

(b) Thermit

(c) Submerged arc

(d) Oxyacetylene

Answer: A

Resistance

Question 18 :

Cores are used

(a) To get cavity or recess in a casting

(b) To get smooth surface on castings

(c) To make castings sound

(d) In symmetrical casting only

Answer: A

To get cavity or recess in a casting

Question 19 :

In climb milling

(a) Tool climbs on the work piece for cutting operations

(b) Work moves in opposite direction as rotation of the cutter tube

(c) Work is fed to cutter in lateral direction

(d) Work moves in same direction as rotation of the cutter

Answer: D

Work moves in same direction as rotation of the cutter

Question 20 :

Which of the following is likely to have highest thermal conductivity?

(a) Solid ice

(b) Steam

(c) Rain water

(d) Distilled water

Answer: A

Solid ice

Question 21 :

The temperature of sun can be measured using a

(a) Mercury thermometer

(b) Platinum resistance thermometer

(c) Radiation pyrometer

(d) Standard thermometer

Answer: C

Radiation pyrometer

Question 22 :

Radiation heat transfer between two surfaces can be reduced by

(a) Introducing radiation shield between the surfaces

(b) Preheating the surfaces closer together

(c) Bringing the surfaces closer together

(d) Polishing the surface

Answer: A

Introducing radiation shield between the surfaces

Question 23 :

The wavelength for maximum emissive power is given by

(a) Stefan Boltzmann law

(b) Wein's law

(c) Fourier's law

(d) Planck's law

Answer: B

Wein's law

Question 24 :

The bulk of tubes at the back of the domestic refrigerator are

(a) Refrigerant cooling tubes

(b) Capillary tubes

(c) Evaporator tubes

(d) Condenser tubes

Answer: D

Condenser tubes

Question 25 :

In which type of single phase motor, the starting torque is low?

(a) Capacitor start and capacitor run type

(b) Capacitor start type

(c) Permanent split capacitor type

(d) Shaded pole type

Answer: D

Shaded pole type

Question 26 :

The critical temperature for Freon 12 is

(a) 0°C

(b) Above 100°C

(c) Around -20°C

(d) Less than -50°C

Answer: B

Above 100°C

Question 27 :

Freon 12 is a compound consisting of atoms of

(a) Carbon, hydrogen and fluorine

(b) Carbon, fluorine and chlorine

(c) Carbon, hydrogen and oxygen

(d) Carbon, hydrogen and fluorine

Answer: B

Carbon, fluorine and chlorine

Question 28 :

True stress is

(a) Average load / original area

(b) Average load / minimum area

(c) Instantaneous load / instantaneous area

(d) Stress calculated on the basis of experimental area

Answer: C

Instantaneous load / instantaneous area

Question 29 :

The instrument used for the measurement of expansion and contraction due to change in temperature, is known as

(a) Tellurometer

(b) Pedometer

(c) Tellurometer

(d) Dilatometer

Answer: D

Dilatometer

Question 30 :

Discoloration should be avoided while handling

(a) Zinc oxide

(b) Starch

(c) Tobacco

(d) Silica flour

Answer: A

Zinc oxide

Question 31 :

Which one of the following statements is correct?

(a) Efficiency of the Carnot cycle is low and work ratio is also low in comparison to the Rankine cycle

(b) Efficiency of the Carnot cycle for thermal power plant is high and work ratio is also high in comparison to the Rankine cycle

(c) Efficiency of the Carnot cycle is high and work ratio is low in comparison to the Rankine cycle

(d) Both the cycle have same efficiencies and work ratio

Answer: C

Efficiency of the Carnot cycle is high and work ratio is low in comparison to the Rankine cycle

Question 32 :

In a steam power plant, the ratio of the isentropic heat drop in the prime mover to the amount of heat supplied per unit mass of steam is known as

(a) Stage efficiency

(b) Rankine efficiency

(c) Degree of reaction

(d) Relative efficiency

Answer: B

Rankine efficiency

Question 33 :

A pantograph is a mechanism with

(a) Lower pairs

(b) Rolling pairs

(c) Turning pairs

(d) Spherical pairs

Answer: A

Lower pairs

Question 34 :

The angle of a V-belt is

(a) 30°

(b) 35°

(c) 40°

(d) 45°

Answer: C

40°

Question 35 :

The governor in which the displacement of the sleeve is high for the small change of speed is known as

(a) Isochronous

(b) Stable

(c) Sensitive

(d) Hunting

Answer: C

Sensitive

Question 36 :

Which of the following, alloy does not contain tin?

(a) White material

(b) Fusible plug material

(c) Phosphor bronze

(d) Gun metal

Answer: A

White material

Question 37 :

Sheradising process is used for

(a) Surface coating

(b) Machining metals

(c) Heat treatment of high speed steels

(d) Heat treatment of steels

Answer: A

Surface coating

Question 38 :

The ratio of thermal conductivity of water to that of ice is nearly

(a) 1 : 2

(b) 1 : 4

(c) 2 : 1

(d) 4 : 1

Answer: B

1 : 4

Question 39 :

Which of the following pollutant result from decaying organic matter?

(a) Ammonia

(b) Acetylene

(c) Nitric oxide

(d) Ozone

Answer: A

Ammonia

Question 40 :

An axial flow compressor is suitable for

(a) Low volume flow rates with low pressure rise

(b) Low volume flow rates with high pressure rise

(c) High volume flow rates with a small pressure rise

(d) High volume flow rates with high pressure rise

Answer: C

High volume flow rates with a small pressure rise

Question 41 :

In axial flow turbines

(a) Water enters radially but leaves axially

(b) Water enters axially and leaves axially

(c) Water enters axially but leaves radially

(d) Water enters radially but leaves axially

Answer: B

Water enters axially and leaves axially

Question 42 :

A negatively skewed curve

(a) Implies that the median will be less than the mean

(b) Implies that mode will be less than the mean

(c) Will have longer tail on the left hand side

(d) Will have longer tail on the right hand side

Answer: C

Will have longer tail on the left hand side

Question 43 :

In India, the work for standardization of production has been mainly done by

(a) BIS

(b) SI

(c) IPC

(d) Survey of India

Answer: A

BIS

Question 44 :

The control system of any automated machine tool involves which of the following basic elements?

(a) Logic

(b) Memory

(c) An input in interface

(d) All of the above

Answer: D

All of the above

Question 45 :

The term used to represent the recycling of unused memory is

(a) Memory dump

(b) Direct memory access

(c) Diagnostic routine

(d) Garbage collection

Answer: D

Garbage collection

Question 46 :

Baud in a binary system is

(a) One bit per second

(b) Two bits per second

(c) Four bits per second

(d) Eight bits per second

Answer: A

One bit per second

Question 47 :

Eddy currents

(a) Increase with fourth power of frequency

(b) Increase with cube of frequency

(c) Increase with square of frequency

(d) Increase with frequency

Answer: C

Increase with square of frequency

Question 48 :

Which allotropic form of iron does not have body centered cubic lattice?

(a) Alpha iron

(b) Beta iron

(c) Delta iron

(d) Gamma iron

Answer: D

Gamma iron

Question 49 :

The principle on which a disappearing filament type pyrometer work is known as

(a) Wien's law

(b) Fourier's law

(c) Kirchhoff's law

(d) Peltier effect

Answer: A

Wien's law

Question 50 :

A hydrometer is used to determine

(a) Buoyancy force

(b) Specific gravity of liquids

(c) Relative humidity

(d) Viscosity of liquids

Answer: B

Specific gravity of liquids