DRDO CEPTAM Technician (Tech-A) Tier-2 Mock Test – Mechanical Trade

Instructions:

Total Questions: 50
Marks: 50
Time: 60 minutes
Each question carries 1 mark
All questions are objective type (MCQs)
No negative marking

Topics Covered:

Engineering Mechanics
Strength of Materials
Thermal Engineering
Fluid Mechanics
Manufacturing & Workshop Technology
Basic Electrical & Instrumentation (mechanical applications)

Part 1 – Engineering Mechanics & Strength of Materials (Questions 1–15)

Q1. A simply supported beam of span 6 m carries a uniformly distributed load of 6 kN/m. The maximum bending moment is:

A. 54 kNm
B. 36 kNm
C. 18 kNm
D. 72 kNm

Q2. A hollow circular shaft has an outer diameter of 50 mm and inner diameter of 30 mm. The polar moment of inertia (J) is:

A. 4.91 × 10⁻⁸ m⁴
B. 5.12 × 10⁻⁸ m⁴
C. 4.91 × 10⁻⁶ m⁴
D. 5.12 × 10⁻⁶ m⁴

Q3. The factor of safety is defined as:

A. Maximum stress / Working stress
B. Yield stress / Working stress
C. Ultimate stress / Working stress
D. All of the above

Q4. A cantilever beam of length 2 m carries a point load of 1 kN at free end. The deflection at the free end is 10 mm. If the load is doubled, the deflection becomes:

A. 10 mm
B. 15 mm
C. 20 mm
D. 40 mm

Q5. The relationship between modulus of elasticity (E), modulus of rigidity (G), and Poisson’s ratio (ν) is:

A. $E = 2G(1 + \nu)$ E=2G(1+ν)
B. $E = G(1 + \nu)$ E=G(1+ν)
C. $E = 3G(1 – 2\nu)$ E=3G(1−2ν)
D. $E = 2G(1 – \nu)$ E=2G(1−ν)

Q6. In torsion of a circular shaft, the maximum shear stress occurs:

A. At the center
B. At the surface
C. At ¼ radius
D. Uniform along radius

Q7. A steel rod of length 2 m and cross-section 50 mm² is subjected to an axial tensile load of 10 kN. If E = 200 GPa, the elongation is:

A. 1 mm
B. 2 mm
C. 0.5 mm
D. 0.2 mm

Q8. Which of the following is a ductile material?

A. Cast iron
B. Brass
C. Grey cast iron
D. Glass

Q9. The maximum bending stress in a simply supported beam with UDL is given by:

A. $\frac{wL^2}{8}$ 8wL2
B. $\frac{wL^2}{12}$ 12wL2
C. $\frac{wL^2}{16}$ 16wL2
D. $\frac{wL^2}{24}$ 24wL2

Q10. A bar of circular cross-section is subjected to torque T. The angle of twist θ is proportional to:

A. $TL / GJ$ TL/GJ
B. $T / LJ$ T/LJ
C. $GJ / TL$ GJ/TL
D. $T / GJL$ T/GJL

Q11. Which failure theory is generally used for ductile materials?

A. Maximum principal stress theory
B. Maximum shear stress theory (Tresca)
C. Rankine theory
D. Coulomb theory

Q12. For a column with pinned ends, the effective length factor (K) is:

A. 0.5
B. 1.0
C. 1.5
D. 2.0

Q13. Modulus of resilience is defined as:

A. Energy absorbed per unit volume up to fracture
B. Energy absorbed per unit volume up to yield
C. Load / Deflection
D. Stress / Strain

Q14. A simply supported beam with span L is subjected to central point load P. Maximum bending moment occurs at:

A. Supports
B. Quarter span
C. Mid-span
D. One-third span

Q15. The slenderness ratio of a column is defined as:

A. Effective length / Radius of gyration
B. Radius of gyration / Effective length
C. Square of effective length / Radius of gyration
D. None of the above

art 2 – Thermal, Fluid, and Manufacturing (Questions 16–35)

Q16.

The Carnot engine efficiency depends on:

A. Working substance
B. Temperature of reservoirs
C. Heat capacity of working substance
D. Pressure of the system

Q17.

Boiling point of water decreases at high altitudes because:

A. Atmospheric pressure decreases
B. Temperature decreases
C. Humidity increases
D. Heat capacity decreases

Q18.

The thermal conductivity of a material indicates:

A. Rate of heat transfer through it
B. Specific heat capacity
C. Thermal expansion
D. Heat absorption

Q19.

A heat engine absorbs 500 J and does 200 J of work. Its efficiency is:

A. 20%
B. 40%
C. 50%
D. 60%

Q20.

Which of the following is a prime mover in thermal plants?

A. Steam turbine
B. Gear pump
C. Lathe machine
D. Hydraulic press

Q21.

In a hydraulic system, Pascal’s law states:

A. Pressure acts only vertically
B. Pressure applied on a confined fluid is transmitted equally in all directions
C. Fluid flows from high to low pressure
D. Pressure depends on velocity

Q22.

Reynolds number helps to predict:

A. Pressure drop
B. Flow type – laminar or turbulent
C. Heat transfer
D. Pump efficiency

Q23.

The viscosity of a fluid:

A. Increases with temperature for liquids
B. Decreases with temperature for liquids
C. Is independent of temperature
D. Depends only on density

Q24.

Which welding method uses an electric arc between electrode and workpiece?

A. Gas welding
B. Arc welding
C. Friction welding
D. Resistance welding

Q25.

A lathe machine is mainly used for:

A. Drilling
B. Turning
C. Milling
D. Grinding

Q26.

Which casting process is suitable for complex geometries?

A. Sand casting
B. Die casting
C. Investment casting
D. Centrifugal casting

Q27.

Annealing of steel is done to:

A. Increase hardness
B. Reduce ductility
C. Increase toughness and remove stresses
D. Harden the surface

Q28.

The main function of a gear pump is:

A. Compress gas
B. Transfer fluid
C. Increase pressure of solids
D. Generate electricity

Q29.

In a nozzle, velocity of fluid increases when:

A. Pressure increases
B. Cross-sectional area decreases
C. Temperature increases
D. Fluid is viscous

Q30.

Which type of boiler is suitable for high-pressure steam generation?

A. Lancashire boiler
B. Babcock and Wilcox boiler
C. Cochran boiler
D. Cornish boiler

Q31.

A manometer measures:

A. Force
B. Temperature
C. Pressure
D. Flow rate

Q32.

In centrifugal pump, maximum head is produced at:

A. Eye of impeller
B. Periphery of impeller
C. Shaft
D. Suction pipe

Q33.

Milling operation is performed on:

A. Lathe machine
B. Milling machine
C. Shaper
D. Drilling machine

Q34.

Which of the following is a non-traditional machining process?

A. Drilling
B. Grinding
C. Electrical Discharge Machining (EDM)
D. Turning

Q35.

Surface hardening of steel can be done by:

A. Carburizing
B. Annealing
C. Normalizing
D. Tempering

Part 3 – Electrical, Measurement & Instrumentation (Questions 36–50)

Q36.

Ohm’s law states that:

A. Voltage = Current × Resistance
B. Current = Voltage × Resistance
C. Power = Voltage × Resistance
D. Voltage = Resistance / Current

Q37.

The unit of electrical resistance is:

A. Volt
B. Ampere
C. Ohm
D. Watt

Q38.

Which device is used to measure electrical current?

A. Voltmeter
B. Ammeter
C. Wattmeter
D. Ohmmeter

Q39.

A single-phase AC supply has a frequency of:

A. 25 Hz
B. 50 Hz
C. 60 Hz
D. 100 Hz

Q40.

Which instrument measures the pressure of fluids in mechanical systems?

A. Manometer
B. Dynamometer
C. Pyrometer
D. Tachometer

Q41.

A strain gauge measures:

A. Force
B. Displacement
C. Strain or deformation
D. Temperature

Q42.

Which sensor is commonly used for temperature measurement in mechanical systems?

A. Thermistor
B. LVDT
C. Tachometer
D. Manometer

Q43.

In a mechanical system, a tachometer measures:

A. Torque
B. Speed or RPM
C. Temperature
D. Pressure

Q44.

Which electrical device converts mechanical energy into electrical energy?

A. Motor
B. Generator
C. Transformer
D. Rectifier

Q45.

A dynamometer is used to measure:

A. Torque
B. Temperature
C. Pressure
D. Flow

Q46.

Which type of connection is used to measure high voltages safely?

A. Series
B. Parallel
C. Voltage divider
D. Direct connection

Q47.

The main function of a relay is to:

A. Store energy
B. Convert AC to DC
C. Control circuits automatically
D. Measure resistance

Q48.

LVDT (Linear Variable Differential Transformer) is used to measure:

A. Linear displacement
B. Angular velocity
C. Pressure
D. Temperature

Q49.

A pressure gauge with a Bourdon tube works on the principle of:

A. Elastic deformation
B. Electromagnetic induction
C. Hydrostatic pressure
D. Capillary action

Q50.

Which instrument is used for calibrating mechanical measuring tools?

A. Vernier caliper
B. Gauge block
C. Screw gauge
D. Dial indicator

Q.No	Answer	Q.No	Answer	Q.No	Answer	Q.No	Answer
1	B	14	C	27	C	40	A
2	A	15	A	28	B	41	C
3	D	16	B	29	B	42	A
4	C	17	A	30	B	43	B
5	A	18	A	31	C	44	B
6	B	19	B	32	B	45	A
7	B	20	A	33	B	46	C
8	B	21	B	34	C	47	C
9	A	22	B	35	A	48	A
10	A	23	B	36	A	49	A
11	B	24	B	37	C	50	B
12	B	25	B	38	B
13	B	26	C	39	B

Disclaimer

This mock test is created for educational and practice purposes only. All questions are original and designed to simulate the DRDO CEPTAM Mechanical Tier-2 trade test pattern. This website is not affiliated with or endorsed by the Defence Research and Development Organisation (DRDO).