Explore topic-wise MCQs in Mechanical Engineering.

This section includes 455 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.

1.

The advantage of thermit welding is that

A. all parts of the weld section are molten at the same time
B. weld cools almost uniformly
C. results in a minimum problem with internal residual stresses
D. all of the above
Answer» E.
2.

When the dimension is expressed as , then the tolerance is

A. 0.035 mm
B. 0.025 mm
C. 0.01 mm
D. 0.06 mm
Answer» E.
3.

The most preferred process for casting gas turbine blades is

A. die casting
B. shell moulding
C. investment moulding
D. sand casting
Answer» C. investment moulding
4.

Thermit, used in thermit welding, is a mixture of

A. charcoal and iron oxide
B. charcoal and aluminium
C. iron oxide and aluminium
D. charcoal, iron oxide and aluminium
Answer» D. charcoal, iron oxide and aluminium
5.

The electrode tip diameter () in spot welding should be equal to (where = Thickness of plate to be welded)

A. 1.5
B. 3
C. 6
Answer» E.
6.

When the dimension is expressed as , then the basic size is

A. 20 mm
B. 20.035 mm
C. 20.025 mm
D. 19.975 mm
Answer» B. 20.035 mm
7.

When the dimension is expressed as , then the basic size is

A. 20 mm
B. 20.035 mm
C. 20.025 mm
D. 19.975 mm
Answer» B. 20.035 mm
8.

When the dimension is expressed as , then the tolerance is

A. 0.035 mm
B. 0.025 mm
C. 0.01 mm
D. 0.06 mm
Answer» E.
9.

According to Indian standards, the total number of tolerance grades are

A. 8
B. 12
C. 18
D. 20
Answer» D. 20
10.

According to Indian standard specifications, 100 H6/g 5 means that.

A. basic size is 100 mm
B. actual size is 100 mm
C. difference between the actual size and basic size is 100 mm
D. none of the above
Answer» B. actual size is 100 mm
11.

In order to check the clearance between two mating surfaces, a __________ gauge should be used.

A. ring
B. plug
C. feeler
Answer» D.
12.

The difference between the upper limit and lower limt of a dimension is called

A. nominal size
B. basic size
C. actual size
D. tolerance
Answer» E.
13.

A file with 50 - 60 teeth in 25 mm is called bastard file.

A. True
B. False
Answer» C.
14.

The length of hacksaw blade is the distance between the outside edges of the holes which fits over the pins.

A. Agree
B. Disagree
Answer» B. Disagree
15.

The width of slot cut by a hacksaw blade is __________ the width of the blade.

A. equal to
B. less than
C. greater than
Answer» D.
16.

For cutting brass, the hacksaw blade should have __________ teeth per 25 mm.

A. 14
B. 24
C. 32
D. 40
Answer» B. 24
17.

In order to cut mild steel, the cutting angle of chisel should be

A. 30°
B. 45°
C. 50°
D. 60°
Answer» E.
18.

A process used for making thin phosphate coating on steel is called parkerising.

A. Correct
B. Incorrect
Answer» B. Incorrect
19.

The torch used for oxygen cutting is same as for oxy-acetylene welding.

A. Yes
B. No
Answer» C.
20.

The vertical welding do not require plate edge preparation upto 16 mm thickness.

A. Correct
B. Incorrect
Answer» B. Incorrect
21.

In back-hand welding, the angle between the welding rod and the work is __________ as compared to fore-hand welding.

A. same
B. less
C. more
Answer» B. less
22.

In fore-hand welding, the angle between the welding torch and the work is __________ as compared to back-hand welding.

A. same
B. less
C. more
Answer» D.
23.

In fore-hand welding, the angle between the welding rod and the work is kept as

A. 30°-40°
B. 40°-50°
C. 50°-60°
D. 60°-70°
Answer» B. 40°-50°
24.

When the weld is made from left to right, it is known as back-hand welding.

A. Agree
B. Disagree
Answer» B. Disagree
25.

In fore-hand welding, the weld is made

A. from left to right
B. from right to left
C. first from left to right and then from right to left
D. either from left to right or from right to left
Answer» C. first from left to right and then from right to left
26.

If neutral flame is used in oxy-acetylene welding, both oxygen and acetylene cylinders of the same capacity will be emptied at the same time.

A. Correct
B. Incorrect
Answer» B. Incorrect
27.

In a gas welding of mild steel using an oxy-acetylene flame, the total amount of acetylene consumed is 10 litre. The oxygen consumption from the cylinder is

A. 5 litre
B. 10 litre
C. 15 litre
D. 20 litre
Answer» C. 15 litre
28.

An oxidising flame is obtained when equal volumes of oxygen and acetylene are supplied.

A. True
B. False
Answer» C.
29.

The brass and bronze are welded by __________ flame.

A. neutral
B. oxidising
C. carburising
D. all of these
Answer» C. carburising
30.

Neutral flame is usd to weld

A. steel
B. cast iron
C. copper
D. all of these
Answer» E.
31.

When more volume of acetylene and less volume of oxygen is supplied, then a __________ flame is obtained.

A. neutral
B. oxidising
C. carburising
Answer» D.
32.

The oxidising flame is similar to neutral flame but the inner cone is less luminous and shorter.

A. Yes
B. No
Answer» B. No
33.

Most of the oxy-acetylene welding is done with

A. neutral flame
B. oxidising flame
C. carburising flame
D. all of these
Answer» B. oxidising flame
34.

For gas welding, the presure desired at the welding torch for acetylene is

A. 7 to 103 kN/m2
B. 70 to 280 kN/m2
C. 280 to 560 kN/m2
D. 560 to 840 kN/m2
Answer» B. 70 to 280 kN/m2
35.

The oxy-acetylene gas used in gas welding produce a flame temperature of

A. 1800°C
B. 2100°C
C. 2400°C
D. 3200°C
Answer» E.
36.

In welding aluminium with TIG arc welding, alternating current is used.

A. Correct
B. Incorrect
Answer» B. Incorrect
37.

In welding magnesium with TIG arc welding, direct current with __________ is used.

A. straight polarity
B. reversed polarity
Answer» C.
38.

In tungsten-inert gas arc welding, a __________ electrode is used.

A. consumable
B. non-consumable
Answer» C.
39.

A large electrode is used in un-shielded arc welding.

A. Correct
B. Incorrect
Answer» B. Incorrect
40.

The welding set up is said to have reversed polarity when the work is connected to the negative terminal and the electrode holder to the positive terminal.

A. Agree
B. Disagree
Answer» B. Disagree
41.

When two metal pieces of different thicknesses are to be welded by projection welding, then the projections should be made on __________ metal piece.

A. thinner
B. thicker
Answer» C.
42.

When two pieces of different metals are to be welded by projection welding, then the projection should be made on the metal piece having __________ conductivity.

A. lower
B. higher
Answer» C.
43.

Seam weiding is a

A. continuous spot welding process
B. multi-spot welding process
C. arc welding process
D. process used for joining round bars
Answer» B. multi-spot welding process
44.

In spot welding, the spacing between two spot weld should not be less than

A. d
B. 1.5 d
C. 3 d
D. 6 d
Answer» D. 6 d
45.

In spot welding, the distance between the nearest edge of the plate and centre of weld should be equal to

A. d
B. 1.5 d
C. 3 d
D. 6 d
Answer» C. 3 d
46.

In electric resistance welding, pressure is applied just after the completion of current.

A. True
B. False
Answer» B. False
47.

In bending operation, the metal takes the shape of a punch.

A. Yes
B. No
Answer» B. No
48.

In a __________ , both cutting and non-cutting operations are performed at one station of the press in every stroke of the ram.

A. simple die
B. progressive die
C. combination die
D. compound die
Answer» D. compound die
49.

In a __________ , two or more operations are performed simultaneously at the single stroke of the ram.

A. simple die
B. progressive die
C. combination die
D. compound die
Answer» C. combination die
50.

The operation of giving impressions of figures, letters or designs on sheet metal parts, is known as embossing.

A. Correct
B. Incorrect
Answer» B. Incorrect