Explore topic-wise MCQs in Mechanical Engineering.

This section includes 346 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.

251.

In latitude 25.0 S, SA (spin axis) of a FG (free gyro) is in position S40E and horizontal. Find the tilt after 6 hours.

A. 61.16 up
B. 61.16 down c) 51.15 up
C. d) none of the mentioned
Answer» B. 61.16 down c) 51.15 up
252.

Calculate the work done per minute by a punch tool making 20 working strokes per min when a 30 mm diametre hole is punched in 5 mm thick plate with ultimate shear strength og 450 Mpa in each stroke.

A. 10.69 knm
B. 20.69 knm
C. 30.69 knm
D. 40.69 knm
Answer» B. 20.69 knm
253.

Power is transmitted by an electric motor to a machine by using a belt drive. The tensions on the tight and slack side of the belt are 2200 N and 1000 N respectively and diameter of the pulley is 600 mm. If speed of the motor is 1500 r.p.m, find the power transmitted.

A. 46.548 kw
B. 56.548 kw
C. 66.548 kw
D. 76.548 kw
Answer» C. 66.548 kw
254.

6 x 10 = 6 rad/s.

A. 2.055 m
B. 3.055 m
C. 4.055 m
D. 5.055 m
Answer» B. 3.055 m
255.

The pitching of a ship is assumed to take place with simple harmonic motion.

A. true
B. false
Answer» B. false
256.

The rotor of a ship rotates in clockwise direction when viewed from stern and the ship takes a right turn. The effect of gyroscopic couple acting on it will be to raise the stern and lower the bow.

A. true
B. false
Answer» B. false
257.

The rolling of a complete ship side-ways is known as pitching of a ship.

A. true
B. false
Answer» C.
258.

The steering of a ship means

A. movement of a complete ship up and down in vertical plane about transverse axis
B. turning of a complete ship in a curve towards right or left, while it moves forward
C. rolling of a complete ship side-ways
D. none of the mentioned
Answer» C. rolling of a complete ship side-ways
259.

The engine of an aeroplane rotates in clockwise direction when seen from the tail end and the aeroplane takes a turn to the left. The effect of gyroscopic couple on the aeroplane will be

A. to dip the nose and tail
B. to raise the nose and tail
C. to raise the nose and dip of the tail
D. to dip the nose and raise the tail
Answer» D. to dip the nose and raise the tail
260.

A disc is a spinning with an angular velocity ω rad/s about the axis of spin. The couple applied to the disc causing precession will be

A. 1/2 iω2
B. iω2
C. 1/2 iωωp
D. iωωp
Answer» E.
261.

Which of the following is a pendulum type governor?

A. watt’s governor
B. porter governor
C. hartnell governor
D. none of the mentioned
Answer» B. porter governor
262.

A Watt’s governor is a spring loaded governor.

A. true
B. false
Answer» C.
263.

In a Porter governor, the balls are attached to the extension of lower links.

A. true
B. false
Answer» B. false
264.

When the sleeve of a Porter governor moves downwards, the governor speed

A. increases
B. decreases
C. remains unaffected
D. first increases and then decreases
Answer» C. remains unaffected
265.

A Watt’s governor can work satisfactorily at speeds from

A. 60 to 80 r.p.m
B. 80 to 100 r.p.m c) 100 to 200 r.p.m d) 200 to 300 r.p.m
C. answer: a
D. explanation: a watt’s governor may only
Answer» D. explanation: a watt’s governor may only
266.

A Hartnell governor is a

A. dead weight governor
B. pendulum type governor
C. spring loaded governor
D. inertia governor
Answer» D. inertia governor
267.

The height of a Watt’s governor is

A. directly proportional to speed
B. directly proportional to (speed)
C. inversely proportional to speed
D. inversely proportional to (speed)
Answer» E.
268.

Isolation factor is twice the transmissibility ratio.

A. true
B. false
Answer» C.
269.

Which of the following is true regarding Ɛ>1?

A. transmitted force is greater than applied force
B. transmitted force is less than applied force
C. spring force is less than applied force
D. damping force is less than applied force
Answer» B. transmitted force is less than applied force
270.

If isolation factor is negative, then what is the phase difference between transmitted and disturbing force?

A. 180°
B. 90°
C. 450°
D. 360°
Answer» B. 90°
271.

Which of the following is a type of transmitted force to the foundation?

A. damping force
B. undamping force
C. tensile force
D. torsional force
Answer» B. undamping force
272.

The ratio of the maximum displacement of the forced vibration to the deflection due to the static force, is known as

A. damping factor
B. damping coefficient
C. logarithmic decrement
D. magnification factor
Answer» E.
273.

When a periodic disturbing force is applied to a machine, the force is transmitted to the foundation by the means of spring.

A. true
B. false
Answer» B. false
274.

The factor which affects the critical speed of a shaft is

A. diameter of the disc
B. span of the shaft
C. eccentricity
D. all of the mentioned
Answer» E.
275.

Which of the following systems produce a vibration in the foundation?

A. unbalanced machine
B. balanced machine
C. coupled machine
D. uncoupled machine
Answer» B. balanced machine
276.

Longitudinal vibrations are said to occur when the particles of a body moves

A. perpendicular to its axis
B. parallel to its axis
C. in a circle about its axis
D. none of the mentioned
Answer» C. in a circle about its axis
277.

When a body is subjected to transverse vibrations, the stress induced in a body will be

A. shear stress
B. bending stress
C. tensile stress
D. compressive stress
Answer» C. tensile stress
278.

In a slider crank mechanism, the length of the crank and connecting rod are 180 mm and 540 mm respectively. The crank position is 45° from inner dead centre. The crank shaft speed is 450 r.p.m. (clockwise), calculate angular velocity of the connecting rod in rad/s.

A. 10.3
B. 11.1
C. 12.2
D. 11.8
Answer» C. 12.2
279.

While calculating angular acceleration of the connecting rod, sin2(θ) term is neglected.

A. true
B. false
Answer» B. false
280.

Which of the following expression represent the angular acceleration α of the connecting rod?

A. −ω2 . sin θ/n
B. −ω2 . cos θ.n
C. ω2. cos θ/n
D. ω2 . sin θ.n
Answer» B. −ω2 . cos θ.n
281.

5 m/s.

A. 4.19
B. 5
C. 3.49
D. 3.36
Answer» D. 3.36
282.

6 kN/m and the damping constant of the damper is 400 Ns/m. If the mass is 50 kg, then the damping factor (d ) and damped natural frequency (fn), respectively, are

A. 0.471 and 1.19 hz
B. 0.471 and 7.48 hz
C. 0.666 and 1.35 hz
D. 0.666 and 8.50 hz
Answer» B. 0.471 and 7.48 hz
283.

The natural frequency of a spring-mass system on earth is ωn. The natural frequency of this system on the moon (gmoon = gearth/6) is

A. ωn
B. 0.408ωn
C. 0.204ωn
D. 0.167ωn
Answer» B. 0.408ωn
284.

The first critical speed of an automobile running on a sinusoidal road is calculated by (modeling it as a single degree of freedom system)

A. resonance
B. approximation
C. superposition
D. rayleigh quotient
Answer» B. approximation
285.

Critical speed is expressed as

A. rotation of shaft in degrees
B. rotation of shaft in radians
C. rotation of shaft in minutes
D. natural frequency of the shaft
Answer» E.
286.

The accelerometer is used as a transducer to measure earthquake in Richter scale. Its design is based on the principle that

A. its natural frequency is very low in comparison to the frequency of vibration
B. its natural frequency is very high in comparison to the frequency of vibration
C. its natural frequency is equal to the frequency of vibration
D. measurement of vibratory motion is without any reference point
Answer» D. measurement of vibratory motion is without any reference point
287.

In vibration isolation system, if ω/ωn < 2, then for all values of damping factor, the transmissibility will be

A. less than unity
B. equal to unity
C. greater than unity
D. zero
Answer» D. zero
288.

The critical speed of a shaft with a disc supported in between is equal to the natural frequency of the system in

A. transverse vibrations
B. torsional vibrations
C. longitudinal vibrations
D. none of the mentioned
Answer» B. torsional vibrations
289.

What is not the effect of unbalanced forces?

A. load on bearings
B. dangerous vibrations
C. stresses in various members
D. violation of conservation of mass principle
Answer» E.
290.

If the unbalanced system is not set right then.

A. static forces develop
B. dynamic forces develop
C. tangential forces develop
D. radial forces develop
Answer» B. dynamic forces develop
291.

In a revolving rotor, the centrifugal force remains balanced as long as the centre of the mass of the rotor lies

A. below the axis of shaft
B. on the axis of the shaft
C. above the axis of shaft
D. away from the axis of shaft
Answer» C. above the axis of shaft
292.

Which of the following is true for centrifugal force causing unbalance?

A. direction changes with rotation
B. magnitude changes with rotation
C. direction and magnitude both change with rotation
D. direction and magnitude both remain unchanged with rotation
Answer» B. magnitude changes with rotation
293.

Balancing of single rotating mass by balancing masses in same plane and in different planes cannot take place.

A. true
B. false
Answer» C.
294.

3 BALANCING MACHINES-FIELD BALANCING OF DISCS AND ROTORS.

A. centripetal forces
B. centrifugal forces
C. friction forces
D. inertia forces
Answer» E.
295.

Compression stroke results in

A. formation of negative loop
B. formation of positive loop
C. formation of an infinite loop
D. formation of no loop
Answer» B. formation of positive loop
296.

When the work is done on the gases, which of the following effect is observed on the turning moment diagram?

A. formation of negative loop
B. formation of positive loop
C. formation of an infinite loop
D. formation of no loop
Answer» B. formation of positive loop
297.

Work produced by the 4-stroke engine is less because

A. one power stroke per 2 revolutions
B. one power stroke per revolution
C. one power stroke per 4 revolution
D. four power stroke per revolution
Answer» B. one power stroke per revolution
298.

4 strokes engine have a lower thermal efficiency than 2 stroke engine.

A. true
B. false
Answer» C.
299.

Secondary forces in reciprocating mass on engine frame are

A. of same frequency as of primary forces
B. twice the frequency as of primary forces
C. four times the frequency as of primary forces
D. none of the mentioned
Answer» C. four times the frequency as of primary forces
300.

Multi-cylinder engines are desirable because

A. only balancing problems are reduced
B. only flywheel size is reduced
C. both (a) and (b)
D. none of the mentioned
Answer» D. none of the mentioned