Junior Engineer • Paper-III (Mechanical Engineering)
The break-even point represents -
A)
The most economical level of operation of any industry
B)
The time when unit can run without loss and profit
C)
Time when industry will undergo loss
D)
The time when company can make maximum profits
Correct answer: B. The time when unit can run without loss and profit is the option that matches the standard principle or definition asked.
Junior Engineer • Paper-III (Mechanical Engineering)
On which of the following just in time(J.LT) manufacturing philosophy emphasizes?
A)
Manpower
B)
Profit
C)
Inventory
D)
Manufacturing
Just-in-Time (JIT) manufacturing philosophy emphasizes minimizing inventory by producing only what is needed, when it is needed, and in the required quantity. Therefore, the correct option is inventory. Manpower is not the main focus of JIT, manufacturing is too broad a term, and profit is an outcome of efficient operations rather than the specific emphasis of JIT.
Junior Engineer • Paper-III (Mechanical Engineering)
Material handling and plant location is analysed by
A)
Bar chart
B)
Bin chart
C)
Emerson chart
D)
Travel chart
Correct answer: D. Travel chart is the option that matches the standard principle or definition asked.
Junior Engineer • Paper-III (Mechanical Engineering)
Which of the following line is the safest in machine design?
A)
Goodman line
B)
Soderberg line
C)
Gerber parabola
D)
Lagrange line
Soderberg line is most conservative below Goodman and Gerber, so safest in design.
Junior Engineer • Paper-III (Mechanical Engineering)
Wahl’s stress factor very rapidly as the spring index decreases.
A)
increases
B)
decreases
C)
remain same
D)
none of these
Wahl factor Kw increases sharply as spring index C=D/d decreases due to curvature.
Junior Engineer • Paper-III (Mechanical Engineering)
The number of bolts by empirical formula in a flange coupling is -
A)
N=2
B)
N= 2.43
C)
N= 3D/4 + 3
D)
N= 2D/5 + 3
Common textbook empirical for flange coupling (D in inches) n=3D/4+3; alternative form n=D/50+3 mm.
Junior Engineer • Paper-III (Mechanical Engineering)
Which of the following is used to form Complex shapes effectively?
A)
Sand casting
B)
Turing
C)
Powder metallurgy
D)
Metal casting
Correct answer: D. Metal casting is the option that matches the standard principle or definition asked.
Junior Engineer • Paper-III (Mechanical Engineering)
Which of the following device is mostly associated with automation?
A)
NC machine
B)
Flexible manufacturing
C)
Computer graphics workstation
D)
Robots
Correct answer: D. Robots is the option that matches the standard principle or definition asked.
Junior Engineer • Paper-III (Mechanical Engineering)
Break-even analysis consists of -
A)
Fixed cost
B)
Variable cost
C)
Fixed and variable cost
D)
Operation cost
Correct answer: C. Fixed and variable cost is the option that matches the standard principle or definition asked.
Junior Engineer • Paper-III (Mechanical Engineering)
Cross-wire welding is -
A)
Multi-spot welding process
B)
Continuous spot welding process
C)
Used to form mesh
D)
Used where additional strength is desired
Correct answer: C. Used to form mesh is the option that matches the standard principle or definition asked.
Junior Engineer • Paper-III (Mechanical Engineering)
The process of chamfering the entrance of a drilled hole is known as
A)
Counter-fillet
B)
Trepanning
C)
Counter-boring
D)
Counter-sinking
Counter-sinking produces a conical/chamfered entrance at the mouth of a drilled hole.
Junior Engineer • Paper-III (Mechanical Engineering)
Ina flange coupling, the bolts are subjected to -
A)
Tensile stress
B)
Shear stress
C)
Compressive stress
D)
Both (a) & (c)
Flange coupling bolts transmit torque by shear, so subjected to shear stress.
Junior Engineer • Paper-III (Mechanical Engineering)
What is the process, in which the metal is caused to flow through a restricted orifice to create an extremely elongated strip of uniform and comparatively smaller cross-sectional area, called?
A)
Rolling
B)
Extrusion
C)
Drawing
D)
Spinning
The correct answer is **Extrusion**. In extrusion, a metal billet is forced through a **restricted orifice (die)** so that it comes out as a long product with a **uniform, reduced cross-section**. This matches the description exactly.
Why the others are incorrect:
- **Drawing**: metal is pulled through a die to reduce its cross-section, but the key phrase here is the metal being **caused to flow through a restricted orifice** under pressure, which is characteristic of extrusion.
- **Spinning**: used to form axisymmetric hollow parts like cones or cylinders by rotating a sheet or blank; it does not produce elongated strips through a die.
- **Rolling**: reduces thickness by passing metal between rotating rolls, not through a restricted orifice.
Junior Engineer • Paper-III (Mechanical Engineering)
If it is required to connect two parallel shafts, the distance between whose axes is small and variable, the shafts are coupled by -
A)
Universal joint
B)
Knuckle joint
C)
Oldham’s coupling
D)
Flexible coupling
Oldham's coupling connects parallel shafts with small lateral misalignment variable distance.
Junior Engineer • Paper-III (Mechanical Engineering)
Welding process in which two pieces to be joined are overlapped and placed between two electrodes is known as -
A)
Percussion welding
B)
Projection welding
C)
Seam welding
D)
Spot welding
In spot welding, overlapping sheets are clamped between electrodes and joined at discrete spots.
Junior Engineer • Paper-III (Mechanical Engineering)
The centrifugal tension in the belt depends upon -
A)
tight side tension of belt
B)
slack side tension of belt
C)
velocity of the belt
D)
weight per unit length of belt
Tc = m·v^2, so depends mainly on belt velocity (and mass per length); most asked answer is velocity.
Junior Engineer • Paper-III (Mechanical Engineering)
A thin walled cylindrical vessel of diameter ‘D’ and wall thickness ‘t’ is subjected to pressure ‘P’. The circumferential stress induced is -
A)
pD/2t
B)
pD/4t
C)
pD/t
D)
pD/8t
Hoop stress = pD/2t for thin cylinder, longitudinal = pD/4t.
Junior Engineer • Paper-III (Mechanical Engineering)
Diameter of washer is generally taken -
A)
Equal to nut size
B)
Less than nut size
C)
Bigger than nut size
D)
Any size irrespective of nut size
The diameter of a washer is generally taken bigger than the nut size so that the load from the nut/bolt head is distributed over a larger area and the washer fully covers the nut bearing area. This prevents local crushing of the connected material and improves grip.
Why others are incorrect:
- a) Equal to nut size: not preferred, because the washer should extend beyond the nut to provide proper load distribution.
- b) Less than nut size: incorrect, as it would not adequately support the nut and may not cover the bearing area.
- d) Any size irrespective of nut size: incorrect, because washer size is selected based on the nut/bolt size and required bearing area.
Junior Engineer • Paper-III (Mechanical Engineering)
The work is usually rotated while the drill is fed into the work in -
A)
Hand drilling machine
B)
Radial drilling machine
C)
Deep hole drilling machine
D)
Multiple spindle drilling machine
Correct answer: C. Deep hole drilling machine is the option that matches the standard principle or definition asked.
Junior Engineer • Paper-III (Mechanical Engineering)
Within elastic limit, stress is -
A)
Square root of strain
B)
Directly proportional to strain
C)
Equal to strain
D)
Inversely proportional to strain
Hooke's law: within elastic limit stress directly proportional to strain.
Junior Engineer • Paper-IV (Electronics Engineering)
The antenna characteristic that measures its ability to focus signal is ?
A)
Bandwidth
B)
Gain
C)
Directivity
D)
Impedance
Directivity measures ability to focus radiated energy in a direction; gain includes efficiency.
Junior Engineer • Paper-IV (Electronics Engineering)
What is the term for the data communication system within a building or campus?
A)
MAN
B)
LAN
C)
PAN
D)
WAN
LAN covers building/campus; MAN city, WAN wide area.
Junior Engineer • Paper-IV (Electronics Engineering)
A hub is a ___ device.
A)
Networking
B)
Software
C)
Calculating
D)
Cleaning
Hub is a networking device that forwards frames to all ports.
Junior Engineer • Paper-IV (Electronics Engineering)
What was the name of the first network?
A)
ASAPNET
B)
ARPANET
C)
CNNET
D)
NSFNET
ARPANET (1969) was first packet-switching network, precursor to internet.
Junior Engineer • Paper-IV (Electronics Engineering)
How is a single channel shared by multiple signals in a computer network?
A)
multiplexing
B)
phase modulation
C)
analog modulation
D)
digital modulation
Multiplexing shares single channel by multiple signals.
