50 objective practice questions for Aligarh Muslim University Engineering Entrance Exam.
Ques: What fraction of a radioactive material will get disintegrated in a period of two half-lives
(a) Whole
(b) Half
(c) One-fourth
(d) Three-fourth
Ans. (d)
Ques. The binding energy per nucleon of deuterium (1H2) and helium (2He4) are 1.1 MeV and
7.0 MeV respectively. The energy released when two deuterium fuse to form a helium nucleus (2He4) is
(a) 28 MeV
(b) 2.2 MeV
(c) 23.6 MeV
(d) 18.6 MeV
Ans: (c)
Ques. The radioactive decay rate of a radioactive element is found to be 103 disintegrations/second at a certain time. If the half life of the element is one second, the decay rate after three second is
(a) 1000
(b) 250
(c) 1000 / 3
(d) 125
Ans: (d)
Ques. Conversion of ammeter into voltmeter requires
(a) low resistance in series
(b) low resistance in parallel
(c) high resistance in series and removal of shunt
(d) a low resistance either in series or in parallel
Ans: (c)
Ques. Which mirror is to be used to obtain a parallel beam of light from a small lamp?
(a) Plane mirror
(b) Convex mirror
(c) Concave mirror
(d) Any one of the above
Ans: (c)
Related: Kinetic theory of gases questions
Ques. Infrared radiation was discovered in 1800 by :
(a) William Wollaston
(b) William Herschel
(c) Wilhelm Roentgen
(d) Thomas Young
Ans: (b)
Ques. The potential to which a conductor is raised, depends on :
(a) the amount of charge
(b) geometry and size of the conductor
(c) both (a) and (b)
(d) only on (a)
Ans: (c)
Ques. In the absence of intermolecular forces of attraction, the observed pressure P will be
(a) P
(b) < P
(c) > P
(d) zero
Ans: (c)
Ques. The optical path of a monochromatic light is same if it goes through 4.0 cm of glass of 4.5 cm of water. If the refractive index of glass is 1.53, the refractive index of the water is.
(a) 1.30
(b) 1.36
(c) 1.42
(d) 1.46
Ans: (b)
Ques. A rocket of mass 1000 kg is exhaust gases at a rate of 4 kg/s with a velocity 3000 m/s. The thrust developed on the rocket is :
(a) 12000 N
(b) 120 N
(c) 800 N
(d) 200 N
Ans: (a)
Ques. The refractive indices of flint glass for red and violet light are 1.613 and 1.632 respectively. Find the angular dispersion produced by a thin prism of flint glass having refracting angle 5o.
(a) 1o
(b) 2o
(c) 0.95o
(d) 0.095o
Ans: (d)
Ques. The two slits in Young’s double slit experiment have widths in the ratio of 1 : 25. The ratio of the intensities of maxima and minima in the interference pattern is
(a) 5/3
(b) 7/5
(c) 9/4
(d) 3/2
Ans: (c)
Ques. The extension in a string obeying Hooke’s low v is x. The speed of sound in the stretched string is v. If the extension in the string is increased to 1.5x, the speed of sound will be
(a) 1.22 v
(b) 0.61 v
(c) 1.50 v
(d) 0.75 v
Ans: (a)
Ques. A magnet makes 30 oscillations per minute at a plane where intensity is 32 T. At another place it takes 1s to complete one oscillation. The value of horizontal intensity at the second place is
(a) 12.8 T
(b) 25.6 T
(c) 128 T
(d) 256 T
Ans: (c)
Related: Atomic Structure Practice Questions
Ques. An optically active compound
(a) rotates the plane polarized light
(b) changes the direction of polarized light
(c) do not allow plane polarized light to pass through
(d) none of the above
Ans: (a)
Ques. A copper wire and a steel wire of same diameter and length are connected end to end and a force is applied which stretches their combined length by 1 cm. The two wires will have
(a) same stress and strain
(b) different stress and strain
(c) different stress and same strain
(d) same stress and different strain
Ans. (d)
Ques. A number of small drops of mercury coalesce to form a single drop. The temperature of the drop will
(a) increase
(b) remain same
(c) decrease
(d) depend on size
Ans: (a)
Ques. When an ideal diatomic gas is heated at constant pressure the fraction of the heat energy supplied which increases the internal energy of the gas is
(a) 2/5
(b) 3/5
(c) 3/7
(d) 5/7
Ans: (d)
Ques. The radii of two spheres are a and b respectively. They are at equal electric potential. The ratio of their surface density of charge is :
(a) a2 / b2
(b) b/a
(c) a/b
(d) b2/a2
Ans: (b)
Ques. In an inductor of self-inductance L = 2 mH, current changes with time according to relation I = t2 e–t. At what time e.m.f. is zero?
(a) 4 s
(b) 3 s
(c) 2 s
(d) 1 s
Ans: (c)
Ques. A force of 5 N acts on a body of 5 kg for 1 second and gives it a momentum p and kinetic energy E. If the same force accelerates the same body through 1 m, the momentum and energy attained by the body are p¢ and E¢ respectively, then the correct relation is
(a) p > p¢, E > E¢
(b) p < p¢, E < E¢
(c) p > p¢, E < E¢
(d) p < p¢, E > E¢
Ans: (b)
Ques. The rms speed of the particles of fume of mass 5 × 10–17 kg executing Brownian motion in air at N.T.P. is (Boltzmann constant, k = 1.4 × 10–23 J/K )
(a) 1.5 m/s
(b) 3.0 m/s
(c) 1.5 cm/s
(d) 3 cm/s
Ans: (c)
Ques. The unit of CR2 is:
(a) Henry
(b) Volt-meter
(c) Joule/ampere
(d) None
Ans. (a)
Ques. A water barrel stands on a table of height h. If a small hole is punched in the side of the barrel at its base, it is found that the resultant stream of water strikes the ground at a horizontal distance R from the table. What is the depth of water in the barrel?
(a) R2/h
(b) R2/2h
(c) R2/4h
(d) 4R2/h
Ans. (c)
Related: Gravitation (Physics) Sample paper
Ques. The dimension of (h/e) [h = plank’s constant and e = electronic charge) are same as that of:
(a) Magnetic field
(b) Magnetic flux
(c) Electric field
(d) Electric flux
Ans: (b)
Ques. The slope of the kinetic energy versus position vector gives the time rate of change of
(a) force
(b) momentum
(c) power
(d) work
Ans: (b)
Ques. A charge q1 exerts certain force on a second charge q2. If third charge q3 is brought near, the force of q1 exerted on q2
(a) decreases
(b) increases
(c) remain unchanged
(d) increases if q3 is of same sign as q1 decreases if q2 is of opposite sign
Ans: (c)
Ques. In an ammeter 10% of main current is passing through the galvanometer. If the resistance of the galvanometer is G, then the shunt resistance, in ohms is:
(a) 9 G
(b) G/9
(c) 90 G
(d) G/90
Ans: (b)
Ques. The disc of a siren containing 60 holes rotates at a constant speed of 360 rpm. The emitted sound is in unison with a tuning fork of frequency :
(a) 10 Hz
(b) 360 Hz
(c) 216 Hz
(d) 60 Hz
Ans: (b)
Ques. Electron of mass m and charge q is travelling with a speed v along a circular path of radius r at right angles to a uniform magnetic field of intensity B. If the speed of the electron is doubled and the magnetic field is halved the resulting path would have a radius :
(a) 2r
(b) 4r
(c) r/4
(d) r/2
Ans: (b)
Ques. The energy that should be added to an electron to reduce its de-Broglie wavelength from 1 nm to 0.5 nm is :
(a) four times the initial energy
(b) equal to the initial energy
(c) twice the initial energy
(d) thrice the initial energy
Ans: (d)
Ques. The relative humidity on a day when partial pressure of water vapour is 0.012 x 105 Pa at 120C is (Take vapour pressure of water at this temperature as 0.016 x 105 Pa)
(a) 70%
(b) 40%
(c) 75%
(d) 25%
Ans: (c)
Ques. A closed organ pipe and an open pipe of the same length produce 4 beats when they are set into vibrations simultaneously. If the length of each of them were twice their initial lengths, the number of beats produced will be
(a) 2
(b) 4
(c) 1
(d) 8
Ans. (a)
Related: Thermodynamics (Physics) Question Bank
Ques. A and B are two radioactive substances whose half–lives are 1 and 2 years respectively. Initially 10 g of A and 1 g of B is taken. The time (approximate) after which they will have same quantity remaining is
(a) 6.62 year
(b) 5 year
(c) 3.2 year
(d) 7 year
Ans: (a)
Ques. Dimensions of gravitational constant are
(a) ML2T2
(b) M1L3T–2
(c) M0L3T2
(d) M–1L3T–2
Ans. (d)
Ques. Two springs have their force constant as k1 and k2 (k1>k2) when they are stretched by same force
(a) no work is done in case of both the springs
(b) equal work is done in case of both the springs
(c) more work is done in case of second spring
(d) more work is done in case of first spring
Ans: (c)
Ques. Fusion reaction takes place at high temperature because :
(a) KE is high enough to overcome repulsion between nuclei
(b) nuclei are most stable at this temperature
(c) nuclei are unstable at this temperature
(d) none of the above
Ans: (a)
Ques. A giant telescope in an observatory has an objective of focal length 19 m and an eye piece of focal length 1 cm. In normal adjustment, the telescope is used to view the moon. What is the diameter of the image of moon formed by objective? The diameter of moon is 3.5 x 106 m and radius of lunar orbit round the earth is 3.8 x 108 m
(a) 10 cm
(b) 12.5 cm
(c) 15 cm
(d) 17.5 cm
Ans: (d)
Ques. When modulation percentage is 75, an AM transmitter produces 10 kw. What would be % power saving if carrier and one of side bands were suppressed before transmission took place?
(a) 90.1%
(b) 89.1%
(c) 88.1%
(d) 87.1%
Ans: (b)
Ques. From the top of a tower of two stones, whose masses are in the ratio 1 : 2 are thrown on straight up with an initial speed u and the second straight down with the same speed u. Then neglecting air resistance :
(a) the heavier stone hits the ground with a higher speed
(b) the lighter stone hits the ground with a higher speed
(c) both the stones will have the same speed when they hit the ground
(d) the speed cannot be determined with the given data
Ans. (c)
Ques. In the absence of intermolecular forces of attraction, the observed pressure P will be
(a) P
(b) < P
(c) > P
(d) zero
Ans: (c)
Ques. Error in the measurement of radius of sphere is 2%. Then error in the calculation of volume will be
(a) 1%
(b) 5%
(c) 3%
(d) 6%
Ans: (d)
Related: Ohm law question
Ques. Two waves having the intensities in the ratio of 9 : 1 produce interference. The ratio of maximum to minimum intensity is equal to
(a) 10 : 8
(b) 9 : 1
(c) 4 : 1
(d) 2 : 1
Ans. (c)
Ques. If two numerically equal forces P and P acting at a point produce a resultant force of magnitude P itself, then the angle between the two original forces is
(a) 0°
(b) 60°
(c) 90°
(d) 120°
Ans: (d)
Ques. The increase in energy of a bar of brass 0.1 m long and of cross-sectional area 1 cm2 when elongated with a load of 10 kg-wt along its length will be
[Y for brass = 1011 N/m2 and g = 10 n/s2]
(a) 5 x 10–5 J
(b) 2.5 x 10–5 J
(c) 52 x 10–5 J
(d) 25 x 10–5 J
Ans: (a)
Ques. A circular hole is made in a steel square plate. The plate is now heated and allowed to expand. Which of the following statements is correct?
(a) Radius of the hole starts to decrease
(b) Radius to the hole starts to increase
(c) Radius of the hole will remain constant
(d) Nothing can be said about change in radius of the hole because ratio of initial radius of hole to initial dimension of the plate is not known
Ans: (b)
Ques. A wave has velocity v in medium P and velocity 2v in medium Q. If the wave is incident in medium P at an angle of 300, then the angle of refraction will be
(a) 300
(b) 450
(c) 600
(d) 900
Ans. (d)
Ques. Magnetic field produced by electrons in atoms and molecules is due to their
(a) spin motion only
(b) orbital motion only
(c) spin and orbital motion both
(d) neither spin nor orbital motion
Ans: (c)
Ques. A flask containing air at 27°C is corked up at atmospheric pressure. The cork can be forced out by a pressure of 2.5 atmosphere. Then to force out the cork, flask should be heated to the temperature of
(a) 150 K
(b) 300 K
(c) 600 K
(d) 750 K
Ans: (d)
Ques. Roads are banked on turns so that
(a) the weight of the vehicle may be decreased
(b) the frictional force between the road and vehicle may be decreased
(c) the wear and tear of tyres may be avoided
(d) to provide necessary centripetal force
Ans: (d)
Related: Coordinate Geometry questions
Ques. An isotope decays to 1/16th of its mass in 1 h. what is the half-life period of the isotope?
(a) 15 min
(b) 30 min
(c) 12 min
(d) 10 min
Ans. (a)
