Generic selectors
Exact matches only
Search in title
Search in content
Search in posts
Search in pages
Filter by Categories
nmims post
Objective Type Set
Online MCQ Assignment
Question Solution
Solved Question
Uncategorized

Multiple choice question for engineering

Set 1

1. The chemical formula of zeolite is
a) FeSO4.7H2O
b) Al2(SO4)3.18 H2O
c) Na2O.Al2O3.xSiO2.yH2O
d) Na2Al2O

View Answer

Answer: c [Reason:] The chemical formula of zeolite is Na2O.Al2O3.xSiO2.yH2O. Zeolites are micro-porous, alumino-silicate minerals commonly used as commercial adsorbents and catalysts.

2. Which of the following is not naturally occurring zeolite?
a) Na+
b) Al+3
c) Si+4
d) Ca+2

View Answer

Answer: d [Reason:] Ca+2 is not naturally occurring zeolite. Na+, Al+3 and Si+4 are some of the naturally occurring zeolites.

3. Natural zeolites are
a) Porous
b) Amorphous
c) Non-durable
d) Possess gel structure

View Answer

Answer: b [Reason:] Natural zeolites are non-porous, amorphous and durable. Natural zeolites form where volcanic rocks and ash layers react with alkaline groundwater.

4. State true or false. Synthetic zeolites possess higher exchange capacity per unit weight compared to natural zeolites.
a) True
b) False

View Answer

Answer: a [Reason:] Synthetic zeolites possess higher exchange capacity per unit weight compared to natural zeolites. Synthetic zeolites are form by a process of slow crystallization of a silica-alumina gel in the presence of alkalis and organic templates.

5. The exhausted zeolite is reclaimed by treating the bed with
a) Conc. NaCl
b) Conc. HCl
c) Conc. H2SO4
d) Dil. HCl

View Answer

Answer: a [Reason:] The exhausted zeolite is reclaimed by treating the bed with conc. NaCl (brine) solution. Zeolites have the potential of providing precise and specific separation of gases including the removal of H2O, CO2 and SO2 from low-grade natural gas streams.

6. Select the incorrect statement from the following option.
a) The capital cost for zeolite process is high
b) The residual hardness in zeolite process is 0-15 ppm
c) The raw water used should be turbid and acidic
d) Automation is possible in zeolite process

View Answer

Answer: c [Reason:] The raw water used should be non-turbid and non-acidic. All the other options are correct. The capital cost for zeolite process is high and the residual hardness in zeolite process is 0-15 ppm. Automation is also possible in zeolite process.

7. In zeolite process, the exchange of ___________ takes place.
a) Anions
b) Cations
c) Both cations and anions
d) No ions exchange

View Answer

Answer: b [Reason:] In zeolite process, the exchange of only cations takes place. The specific activation modality of most zeolitic catalysts used in petrochemical applications involves quantum-chemical Lewis acid site reactions.

8. The hardness of 1000 litres of a water sample was removed by passing it through a zeolite softener which required 30litres of NaCl solution containing 1.5 gm/L NaCl for regeneration. The hardness of water sample will be
a) 54.2 ppm
b) 12.9 ppm
c) 45 ppm
d) 38.46 ppm

View Answer

Answer: d [Reason:] The hardness of the water sample will be 38.46 ppm.

9. Which of the following cannot be used in place of NaCl?
a) NaNO3
b) KCl
c) HCl
d) KNO3

View Answer

Answer: c [Reason:] NaNO3, KCl and KNO3 can also be used instead of NaCl. But HCl cannot be used in place of NaCl.

10. Natrolite is an example of
a) Synthetic zeolite
b) Natural zeolite
c) Calgon
d) Colloid

View Answer

Answer: b [Reason:] Natrolite is an example of natural zeolite. Natural zeolites are non-porous, amorphous and durable. Natural zeolites form where volcanic rocks and ash layers react with alkaline groundwater.

Set 2

1. A body can have energy without momentum. True or false?
a) True
b) False

View Answer

Answer: a [Reason:] A body can have energy without momentum. There is an internal energy in a body due to the thermal agitation of the particles of the body, while the vector sum if momenta of the moving particle may be zero.

2. A particle is acted upon by a force of constant magnitude which is always perpendicular to the velocity of the particle. The motion of the particle takes place in a plane. It follows that
a) Its velocity is constant and kinetic energy is constant
b) Its acceleration and velocity is constant
c) Its kinetic energy is constant and it moves in a circular path
d) Its acceleration is constant and it moves in a circular path

View Answer

Answer: c [Reason:] For a particle in uniform circular motion, the direction of both velocity and acceleration vectors change continuously but their magnitudes remain unchanged. The kinetic energy is not affected. Hence its kinetic energy is constant and it moves in a circular path.

3. An athlete in the Olympic game covers a distance of 100m in 10s. His kinetic energy can be estimated in the range
a) 200J – 500J
b) 2×105J – 3×105J
c) 20000J – 50000J
d) 2000J – 5000J

View Answer

Answer: d [Reason:] Average speed of the athlete, v = s/t = 10m/s Assuming the mass of the athlete to 60kg, his average kinetic energy would be K = 1/2×60×102 K = 3000J

4. A particle of mass 100g is thrown vertically upwards with a speed of 5m/s. The work done by the force of gravity during the time the particle goes up is
a) 1.25J
b) 0.5J
c) -0.5J
d) -1.25J

View Answer

Answer: d [Reason:] Work done by the force of gravity = Loss in kinetic energy of the body Work done by the force of gravity = 1/2 m(v2-u2) = 1/2×100/1000×(02-52)J Work done by the force of gravity = -1.25J

5. Statement 1: Linear momentum of a system of particles is zero
Statement 2: Kinetic energy of a system of particles is zero
a) 1 does not imply 2 and 2 does not imply 1
b) 1 implies 2 but 2 does not imply 1
c) 1 does not imply 2 but 2 implies 1
d) 1 implies 2 and 2 implies 1

View Answer

Answer: c [Reason:] When the linear momentum of a system of particles is zero, the velocities of the individual particles may not be zero. The kinetic energy of the system of particles may be non-zero. Thus 1 does not imply 2. When the kinetic energy of system of particles is zero, then the kinetic energy and hence the velocity of each particle is zero. Therefore the linear momentum of a system of particles is zero. Thus 2 imply 1.

6. A spherical ball of mass 20kg is stationary at the top of a hill of height 100m. It rolls down a smooth surface to the ground, then climbs up another hill of height 30m and finally rolls done to a horizontal base at a height of 20m above the ground. The velocity attained by the ball is
a) 10m/s
b) 10√30m/s
c) 40m/s
d) 20m/

View Answer

Answer: c [Reason:] Total energy at 100m height = Total energy at 20m height mgh1= mgh2 + 1/2 mv2 v = √(2g(h1-h2) ) = √(2×10×(100-20)) = 40m/s

7. If mass-energy equivalence is taken into account, when water is cooled to form ice, the mass of water should
a) Increase
b) Remain unchanged
c) Decrease
d) First increase and then decrease

View Answer

Answer: a [Reason:] The heat energy possessed by water gets converted into mass, when ice is formed. This increases the mass. Therefore when water is cooled to form ice, then mass of the water should increase.

8. A body moves a distance of 10m under the action of force F = 10N. If the work done is 25 J, the angle which the force makes with the direction of motion is
a) 0°
b) 30°
c) 60°
d) None of these

View Answer

Answer: d [Reason:] W = Fscosθ 25 = 10×10cos⁡θ Cosθ = 1/4 θ = cos(-1) 1/4

9. Two bodies of mass and 4m have equal kinetic energy. What is the ratio of their momentum?
a) 1:4
b) 1:2
c) 1:1
d) 2:1

View Answer

Answer: b [Reason:] p = √2mK For same K, p1/p2 =√(m1/m2 )=√(m/4m)=1/2 = 1:2

Set 3

1. The volume o an auditorium is 12,000m3. Its reverberation time is 1.5 seconds. If the average absorption coefficient of interior surfaces is 0.4 Sabine/m2. Find the area of interior surfaces.
a) 20,000m2
b) 3340m2
c) 4500m2
d) 450m2

View Answer

Answer: b [Reason:] Reverberation time = 0.167V/aS Total surface area S=3340m2

2. The intensity of sound produced by roaring of a lion at a distance of 5m is 0.01W/m2. Calculate the intensity level in decibel.
a) 1dB
b) 11dB
c) 100dB
d) 20dB

View Answer

Answer: c [Reason:] Intensity level = 10log0.01/10-12 Intensity level = 100dB

3. Calculate the intensity level of a plane just leaving the runway having sound intensity of about 1000W/m2.
a) 0dB
b) 15dB
c) 5dB
d) 150dB

View Answer

Answer: d [Reason:] Intensity level = 10log1000/10-12 Intensity level = 150dB

4. Frequency is used for tuning musical instruments. True or false?
a) True
b) False

View Answer

Answer: b [Reason:] Musicians use the beat phenomenon in tuning their musical instruments. If an instrument is sounded against a standard frequency and tuned until the beats disappear, then the instrument is in tune with the standard frequency. Therefore beats are used for tuning musical instruments.

5. A tuning fork produces 4 beats/s when sounded with a tuning fork of frequency 512Hz.The same tuning fork when sounded with another tuning fork of frequency 514Hz produces 6 beats/s. Find the frequency of the tuning fork.
a) 500Hz
b) 1000Hz
c) 128Hz
d) 508Hz

View Answer

Answer: d [Reason:] Let the frequency of tuning fork = v The fork produces 4 beats/s with a tuning fork of frequency 512Hz Therefore, v = 512±4 = 516Hz or 508Hz The fork also produces 6 beats/s with a tuning fork of frequency 514Hz Therefore, v = 514±6 = 520Hz or 508Hz 508Hz is common in both the cases. Therefore, the frequency of the tuning fork is 508Hz.

6. When a train, blowing its whistle, approaches him, the pitch of the whistle appears to rise and it appears to drop as the engine moves away from him. What is the effect observed here?
a) Doppler effect
b) Frequency effect
c) Beats
d) Echelon effect

View Answer

Answer: a [Reason:] Whenever there is a relative motion between the source, the observer and the medium, the frequency of sound emitted by the source as received by the observer is different from the frequency of sound emitted by the source. The apparent change in frequency when the source, the observer and the medium are in motion is called Doppler effect.

7. In which of the following is the Doppler Effect symmetric?
a) Water
b) Air
c) Liquid
d) Light

View Answer

Answer: d [Reason:] Doppler effect is said to be asymmetric. However, Doppler effect in light is symmetric. This is because sound or mechanical waves in general, have a velocity relative to the medium through which they travel whereas light or electromagnetic waves travel quiet and independent of it.

8. What will be the velocity of sound in a perfectly rigid rod?
a) Infinity
b) Finite
c) Zero
d) Constant

View Answer

Answer: a [Reason:] The velocity of sound in a perfectly rigid body will be infinite because the value of Young’s modulus of elasticity is infinite for a perfectly rigid rod.

9. The speed of sound in moist air is greater than that in dry air. True or false?
a) True
b) False

View Answer

Answer: a [Reason:] The density of water vapour is less than that of air. So the density of air mixed with water vapour is less than that of dry air. Hence the speed of sound in moist air is greater than that in dry air.

10. The sound of a bomb explosion travels faster than the sound produced by a humming bee. True or false?
a) True
b) False

View Answer

Answer: b [Reason:] The velocity of sound in a medium does not depend upon its loudness, pitch or quality. Thus the sound of a bomb explosion and the sound produced by humming bee, even though having entirely different characteristics, travel with the same speed.

11. When can sound be heard over long distances?
a) On a sunny day
b) On a humid day
c) When snowing
d) On a rainy day

View Answer

Answer: d [Reason:] On a rainy day, the air contains a larger amount of water vapour. This decreases the density of air. As a result, the sound travels faster in air and can be heard over longer distances.

12. A person riding on a merry-go round emits a sound wave of a certain frequency. Will the person at centre observe Doppler Effect?
a) Yes
b) No

View Answer

Answer: b [Reason:] The person does not experience Doppler Effect because the source is moving perpendicular to the line joining the source and the observer.

Set 4

1. When does a normal conductor become a superconductor?
a) At normal temperature
b) At Curie temperature
c) At critical temperature
d) Never

View Answer

Answer: c [Reason:] The temperature at which a normal conductor loses its resistivity and becomes a super conductor is knows as transition temperature or critical temperature.

2. In which of the following does the residual resistivity exist?
a) Impure metal at high temperature
b) Pure metal at low temperature
c) Pure metal at high temperature
d) Impure metal at low temperature

View Answer

Answer: d [Reason:] When the temperature is reduced to 0K, the resistivity of the impure metal doesn’t become zero, because there exist some impurities which gives rise to minimum resistivity known as residual resistivity.

3. Meissner effect occurs in superconductors due to which of the following properties?
a) Diamagnetic property
b) Magnetic property
c) Paramagnetic property
d) Ferromagnetic property

View Answer

Answer: a [Reason:] A diamagnetic material has a tendency to expel magnetic lines of forces. Since the super conductor also expels magnetic lines of force it behaves as a perfect diamagnet. This behaviour is first observed by Meissner and is hence called Meissner effect.

4. What happens when a large value a.c. current is passed through super conductors?
a) Conductivity increases
b) Superconducting property is destroyed
c) It acts as a magnet
d) It becomes resistant

View Answer

Answer: b [Reason:] When a large value of a.c. current is applied to a super conducting material it induces some magnetic field in the material and because of this magnetic field, the superconducting property of the material is destroyed.

5. How is persistent current produced in supermagnets?
a) By passing ac current
b) By magnetising it
c) By passing dc current
d) By increasing the resistance

View Answer

Answer: c [Reason:] When dc current of large magnitude is once induced in a super conducting ring then the current persists in the ring even after the removal of the field. This current is called persistent current. This is due to diamagnetic property. The magnetic flux inside the ring will be trapped in it and hence current persists.

6. Superconductors can be used as a memory or storage elements in computers. True or false?
a) True
b) False

View Answer

Answer: a [Reason:] Since the current in superconducting ring can flow without any change in its value, it can be used as a memory or storage element in computers.

7. Superconducting tin has a critical temperature of 3.7K at zero magnetic field and a critical field at 0.0306 Tesla at 0K. Find the critical field at 2K.
a) 0.0306 Tesla
b) 7.4 Tesla
c) 0.02166 Tesla
d) 0 Tesla

View Answer

Answer: c [Reason:] Critical field, Hc = H0 [1-T2/(Tc)2 )] Critical college = 0.02166 Tesla

8. Calculate the critical current for a wire of lead having a diameter of 1mm at 4.2 K. Calculate temperature for lead is 7.18 K and Hc = 6.5×104 A/m. Critical field is 42.758×103 A/m.
a) 3.5593 A
b) 27.3 A
c) 46.67 A
d) 134.26 A

View Answer

Answer: d [Reason:] Critical current Ic = 2πrHc Ic = 134.26 A

Set 5

1. A simple pendulum performs simple harmonic motion about x = 0 with an amplitude a and time period T. The speed of the pendulum at x = a/2 will be
a) (πa√3)/T
b) (πa√3)/2T
c) πa/T
d) (3π2 a)/T

View Answer

Answer: a [Reason:] Speed, v=ω√(a2-x2 ),x=a/2 v=ω√(a2-a2/4)=2π/T×(√3 a)/2=(πa√3)/T

2. A body is executing simple harmonic motion. When the displacements from the mean position are 4cm and 5cm, the corresponding velocities of the body are 10cm/sec and 8cm/sec. Then the time period of the body is
a) 2π sec
b) π/2 sec
c) π sec
d) 3π/2 sec

View Answer

Answer: c [Reason:] T=2π√(((x2)2-(x1)2)/((u1)2-(u2)2))=2π√((52-42)/(102-82)) T=2π√(9/36)=2π×3/6=πsec

3. The total energy of a particle performing simple harmonic motion depends on
a) k, a, m
b) k, a
c) k, a, x
d) k, x

View Answer

Answer: b [Reason:] E=1/2×mω2 a2=1/2×ka2 Clearly, E depends on k and a

4. The particle executing simple harmonic motion has a kinetic energy K0 cos2 ωt. The maximum values of the potential energy and the total energy are respectively
a) Kc/2 and K0
b) K0 and K0
c) K0 and 2K0
d) 0 and 2K0

View Answer

Answer: b [Reason:] When kinetic energy is maximum, potential energy is zero and vice-versa. But Kinetic energy+ Potential energy = Total energy Maximum potential energy = Maximum kinetic energy = Total energy = K0

5. A linear harmonic oscillator of force constant 2×106 N/m and amplitude 0.01m has a total mechanical energy of 160J. Its
a) Potential energy is 160 J
b) Potential energy is zero
c) Potential energy is 100J
d) Potential energy is 120J

View Answer

Answer: c [Reason:] Potential energy = 1/2×kx2 =1/2×2×106×0.012=100J

6. The potential energy of a simple harmonic oscillation when the article is halfway to its end point is
a) 2/3 E
b) 1/8 E
c) ¼ E
d) ½ E

View Answer

Answer: c [Reason:] Total energy E = 1/2×ka2 At x = a/2, the potential energy is Potential energy=1/2×k×(a/2)2 =1/4×1/2×ka2=E/4

7. In a simple harmonic motion, when the displacement is one half the amplitude, what fraction of the total energy is kinetic?
a) ½
b) ¾
c) Zero
d) ¼

View Answer

Answer: b [Reason:] At x = a/2, the kinetic energy is Kinetic energy=1/2×k×[a2-(a/2)2 ]=3/4×1/2×ka2=3/4 E

8. A body executes simple harmonic motion with amplitude A. At what displacement from the mean position is the potential energy of the body one fourth of its total energy?
a) A/4
b) A/2
c) 3A/4
d) Some other fraction of A

View Answer

Answer: b [Reason:] Potential energy = 1/4×Total enegry 1/2×kx2=1/4×1/2×kA2 x=A/2

9. A loaded vertical spring executes simple harmonic motion with a time period of 4 sec. The difference between the kinetic energy and potential energy of this system varies with a period of
a) 2 sec
b) 1 sec
c) 8 sec
d) 4 sec

View Answer

Answer: a [Reason:] Here T=4s. In one oscillation, both kinetic energy and potential energy become twice maximum and twice minimum. Hence the difference between kinetic energy and potential 2s.

10. A mass m is vertically suspended from a spring of negligible mass; the system oscillates with a frequency n. What will be the frequency of the system, if a mass 4m is suspended from the same spring?
a) n/2
b) 4n
c) n/4
d) 2n

View Answer

Answer: a [Reason:] Here n=1/2π×√(k/m) n=1/2π×√(k/4m)=n/2

.woocommerce-message { background-color: #98C391 !important; }