Explore topic-wise MCQs in Machine Design.

This section includes 509 Mcqs, each offering curated multiple-choice questions to sharpen your Machine Design knowledge and support exam preparation. Choose a topic below to get started.

101.

Friction losses in spur gears may be of the order of

A. 15% to 20%
B. 20% to 30%
C. 5% to 10%
D. 10% to 15%
E. Less than 5%
Answer» F.
102.

The cam used for high speed engines is

A. Cycloidal
B. Involute
C. Flat
D. Uniform acceleration
E. Tangent
Answer» B. Involute
103.

The period during which a cam follower does not move is known as

A. Free period
B. Swell period
C. Constant period
D. Stationary period
E. Fixed period
Answer» C. Constant period
104.

In order to minimise jerks, the type of cam used is

A. Cycloidal
B. Hyperbolic
C. S.H.M.
D. Cylindrical
E. Parabolic
Answer» B. Hyperbolic
105.

For butt welding of two plates each of which is 25 mm thick, the best process would be

A. Electron slag welding
B. Submerged are welding
C. MIG welding
D. Gas welding
E. TIG welding
Answer» B. Submerged are welding
106.

The stretching in a belt is controlled by

A. Increasing belt velocity
B. Reducing stress in the belt
C. Increasing belt thickness
D. Reducing belt length
E. Increasing centre distance
Answer» C. Increasing belt thickness
107.

When a nut is tightened by placing a washer under it, the bolt tends to fall in

A. compression
B. tension
C. shear
D. none of the above
E. Cast steel
Answer» C. shear
108.

Gears for wrist watches are generally manufactured by

A. Pitcl, angle
B. Helix angle
C. Axial pitch angle
D. Lead angle
E. Pressure angle
Answer» C. Axial pitch angle
109.

The deep bins are the containers in which the plane of rupture intersects

A. the top surface of material stored
B. Increasing the diameter of threaded portion
C. the opposite surface (wall) near the bottom
D. the bottom survace of material stored
E. the opposite face (wall) near the top
Answer» F.
110.

In case of aircraft body the type of welding generally used is

A. Gas welding
B. Arc welding
C. Spot welding
D. Seam welding
E. None of the above
Answer» F.
111.

Jaw clutches are generally used for

A. high horse power low rpm applications
B. low horse power high rpm applications
C. high horse power high rpm applications
D. low horse power low rpm applications
E. Increasing the diameter of threaded portion
Answer» E. Increasing the diameter of threaded portion
112.

Within elastic limits the greatest amount of strain energy per unit volume that a material can absorb is known as

A. Resilience
B. Shock proof energy
C. Proof resilience
D. Impact energy limit
E. Strain hardening
Answer» D. Impact energy limit
113.

A 20 HP 1500 r.p.m. induction motor will take current of nearly

A. 20-30 Amp
B. 5 Amp
C. 1 Amp
D. 10-15 Amp
E. 15-20 Amp
Answer» B. 5 Amp
114.

Which oil has highest specific gravity?

A. Castor
B. Sperm
C. Cotton Seed
D. Petroleum
E. Turpentine
Answer» B. Sperm
115.

The light gauge steel structural members are generally

A. fabricated fromthick sections
B. hot rolled
C. Increasing the diameter of threaded portion
D. cold formed
E. casted
Answer» E. casted
116.

In which component a ball or roller bearing cannot be used?

A. Water circulating pump
B. Wheel bearing in automobiles
C. Small end of connecting rod
D. Carankshaft main bearings
E. Big end of connecting rod
Answer» F.
117.

Within the elastic range, the bulk modulus of elasticity is defined as the ratio of

A. hydrostatic stress to the volumetric strain
B. shearing stress to the shearing strain
C. longitudinal stress to the longitudinal strain
D. none of the above
E. Increasing the diameter of threaded portion
Answer» B. shearing stress to the shearing strain
118.

Which of the following fit can be used for interchangeable assembly

A. 10 kg
B. Tight
C. Sung
D. Medium force
E. Wringing
Answer» D. Medium force
119.

The shock absorbing capacity of a bolt is increased by

A. Proper tightening
B. Use of a spring washer
C. Making shank diameter equal to the core diameter
D. Preventingstress concentration any where in the bolt
E. None of the above
Answer» D. Preventingstress concentration any where in the bolt
120.

A double start screw has

A. Two threads per inch
B. Fine threads
C. Coarse threads
D. Two threads at some phase angle
E. None of the above
Answer» E. None of the above
121.

In general, the bunkers are constructed

A. circular and polygonal in plan
B. square and rectangular in plan
C. Increasing the diameter of threaded portion
D. hexagonal in plan
E. elliptical in plan
Answer» C. Increasing the diameter of threaded portion
122.

When it is desired to transmit a high velocity ratio in a limited space, the device used is

A. Worm and worm wheel
B. Bevel gears
C. Helical gears
D. Noone of the above
E. None of the above
Answer» B. Bevel gears
123.

In flange coupling the weakest element should be

A. Shaft
B. Flange
C. Key
D. Bolts
E. Bolt bush
Answer» D. Bolts
124.

Which of the following has highest strength to weight ratio?

A. Alloy steel, heat treated
B. Brass
C. Stainless steel
D. Steel piano wire
E. Aluminium, hard rolled
Answer» E. Aluminium, hard rolled
125.

A positive infinitely variable (P.I.V.) system utilises

A. Variable pitch chain drive system
B. Hydraulic variable speed drive
C. Rolling contact variable speed
D. Vee belt variable speed system
E. None of the above
Answer» B. Hydraulic variable speed drive
126.

The assumption of bi-linearly idealised stress-strain relationship for plastic analysis and design is used for

A. steel structures
B. Increasing the diameter of threaded portion
C. prestressed concrete structures
D. reinforced concrete structures
E. aluminium structures
Answer» B. Increasing the diameter of threaded portion
127.

Battens in compound steel columns are provided to

A. increase the column capacity
B. ensure unified behaviour
C. prevent buckling
D. Increasing the diameter of threaded portion
E. decrease the buckling in members
Answer» C. prevent buckling
128.

The bending moment at a plastic hinge is

A. equal to zero
B. equal to plastic moment of the section
C. Increasing the diameter of threaded portion
D. equal to yield moment of the section
E. greater than plastic moment of the section
Answer» C. Increasing the diameter of threaded portion
129.

V-belt sections generally used in an automobiles are

A. A and B
B. C
C. D
D. E
E. Any one of the above
Answer» B. C
130.

For a transverse load on a fillet weld of equal legs, the plane of maximum shear force occurs at

A. 72?
B. 75?
C. 45?
D. 30?
E. 67
Answer» F.
131.

The form coefficient of a spring is

A. Dynamic load carrying capacity
B. It capability to store energy
C. The load/unit drflection
D. Load/spring area
E. Ratio of coil diameter to wire diameter
Answer» C. The load/unit drflection
132.

An out-of-plane web distribution is known as

A. column buckling
B. web buckling
C. vertical web buckling
D. any of the above
E. Increasing the diameter of threaded portion
Answer» E. Increasing the diameter of threaded portion
133.

If M 20 coarse pitch is 2.5 mm the mm the fine pitch for the size would be

A. 10 mm
B. 5 mm
C. 2.5 mm
D. 1.5 mm
E. None of the above
Answer» E. None of the above
134.

While designing a shaft, hub and a key, care is taken so that

A. Key is the weakest component
B. Shaft is the stronger component
C. Key is the strongest component
D. Shaft is the weakest component
E. Hub is the strongest component
Answer» B. Shaft is the stronger component
135.

The maximum size of the fillet weld that can be applied to the toe of an angle or the round edge should be

A. 1.5 mm less than the thickness of the plate
B. Increasing the diameter of threaded portion
C. equal to the thickness of the plate
D. 0.75 times the thickness of the plate
E. 1.5 mm more than the thickness of the plate
Answer» E. 1.5 mm more than the thickness of the plate
136.

Which cam profile is preferred for minimum jerks?

A. Flat
B. Involute
C. Cycloidal
D. Simple harmonic
E. Any of the above
Answer» D. Simple harmonic
137.

Treads in tyres are provided to

A. increase tyre grip on the road
B. prevent skidding on dusty roads
C. prevent skidding on wet roads
D. none of the above
E. Cast steel
Answer» C. prevent skidding on wet roads
138.

The stability of a structure is ensured if the restoring moment is

A. equal to
B. greater than
C. Increasing the diameter of threaded portion
D. smaller than
Answer» D. smaller than
139.

The allowable stresses for the design of steel tanks are adopted

A. 80 percent reduced as given in IS : 800
B. 95 percent reduced as given in IS : 800
C. 50 percent reduced as given in IS : 800
D. Increasing the diameter of threaded portion
E. as given in IS : 800
Answer» B. 95 percent reduced as given in IS : 800
140.

The balls in a ball bearing remain in position

A. Due to centrifugal force
B. In a cage
C. Due to dead load on bearing
D. By lubricant
E. Automatically
Answer» C. Due to dead load on bearing
141.

Which of the following alloying metal for steels acts as a deoxidizing and desulphurising agent?

A. Nickel
B. Increasing the diameter of threaded portion
C. Chromium
D. Tungsten
E. Manganese
Answer» E. Manganese
142.

For the same power transmission, V-belts are

A. wider, thinner
B. thinner, wider
C. Increasing the diameter of threaded portion
D. narrow, thicker
E. thicker, narrow
Answer» E. thicker, narrow
143.

The life of a ball bearing is usually given in

A. hours of service
B. total rpm
C. either of (A) or (B) above
D. none of the above
E. Increasing the diameter of threaded portion
Answer» D. none of the above
144.

Which of the following types of gears are free from interference?

A. Cycloidal
B. Epicycloidal
C. Involute
D. Stub
E. Hypocycloidal
Answer» B. Epicycloidal
145.

A cantilever beam of square section is subjected to a load W at the free end. If the length of the beam is increased and load reduced to half the deflection at the free end as compared to original deflection would be

A. 4 times
B. 16 times
C. 1/2 times
D. 2 times
E. 8 times
Answer» B. 16 times
146.

The fatigue limit of a material

A. Is greatly decreased by poor surface conditions
B. Is improved if there is rough surface
C. Is independent of surface conditions
D. Surface defects which extend upto core have no influence of fatigue limits
E. None of the above
Answer» B. Is improved if there is rough surface
147.

A spherical metal vessel 120 cm diameter is subjected to an internal pressure of 15 kg/sq cm. If the permissible stress is 625 kg/sq cm and the efficiency of the riveted joints is 75%, the required thickness of the plate would be

A. 10 mm
B. 2 mm
C. 5 mm
D. 1 mm
E. 8 mm
Answer» B. 2 mm
148.

In a ball bearing a ball is subjected to

A. Compressive stress
B. Tensile stress
C. Shear stress
D. Cyclic stress or fatigue
E. None of the above
Answer» E. None of the above
149.

Backlash is

A. Sum of the clearance of two gears
B. Mutual play between two gears
C. The amount by which the width of a tooth space exceeds the thickness of the engaging tooth on pitch circle
D. Any of the above
E. None of the above
Answer» D. Any of the above
150.

The limit design of steel structures makes use of

A. elastic and plastic analysis of structures
B. ultimate analysis
C. Increasing the diameter of threaded portion
D. plastic analysis of structures
E. elastic analysis of structures
Answer» E. elastic analysis of structures