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SAMPLE
UEE 2017 – PHY / 02 1
UNIVERSITY ENTRANCE EXAMINATION 2017
PHYSICS
Duration : 2 hours
Please read the following instructions carefully.
1. This paper is made up of 50 Multiple-Choice questions and comprises
TWENTY (20) printed pages.
2. Do not write on the question paper.
3. Answer all questions and indicate your answers on the answer sheetprovided. Marks will not be deducted for wrong answers.
4. Do not take any paper, including the question paper or unused answersheets, out of the examination hall.
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USEFUL INFORMATION:
Acceleration due to gravity, 𝑔 ≈ 9.80 m s−2
Avogadro’s number, 𝑁𝐴 ≈ 6.022 × 1023 particles mol⁄
Universal gas constant, 𝑅 ≈ 8.314 J K−1 mol−1
Gravitational constant, 𝐺 ≈ 6.673 × 10−11 N m2 kg−2
Coulomb constant, 𝑘 ≈ 8.99 × 109 N m2 C−2
Magnitude of charge of electron, 𝑒 ≈ 1.602 × 10−19 C
Mass of electron, 𝑚𝑒 ≈ 9.109 × 10−31 kg
Mass of proton, 𝑚𝑝 ≈ 1.673 × 10−27 kg
Mass of neutron, 𝑚𝑛 ≈ 1.675 × 10−27 kg
Speed of light, 𝑐 ≈ 2.998 × 108 m s−1
Planck’s constant, ℎ ≈ 6.626 × 10−34 J s
Atomic mass unit, 𝑢 ≈ 1.661 × 10−27 kg
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Multiple-Choice Questions
Answer all questions in this section.
1. What is the SI unit for the average speed of a car?
A ft B yd C m
D m/s E m/s2
2. A cyclist accelerates down a hill and then travels at constant speed for a
very short time before decelerating, as he climbs up another hill. Which graph possibly shows the variation with time t of the distance s moved by
the cyclist?
A B
C D
E None of the above
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3. A 100 kg cart accelerates at 0.50 m/s2 west as a horse exerts a force of 60 N west on the cart. What is the magnitude of the force that the cart
exerts on the horse?
A 10 N
B 50 N C 60 N D 110 N
E None of the above
4. In 2001, the leaning tower of Pisa in Italy shown on the right was stabilized by a bundle of steel cables anchored to the ground as shown by the following
simplified sketch.
If the weight of the tower is W, the tension in the cable is T and the reaction from the ground is R, which vector triangle best represents the forces acting
on the tower?
A B
C D
E None of the above
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5. Two objects, initially next to each other and at rest, accelerate in the same straight line at different uniform rates. After 3 s, they are 12 m apart. If
they continue to accelerate at the same rate, how far apart will they be 6 s after they started?
A 18 m B 24 m C 36 m
D 48 m E 60 m
6. A projectile will attain its maximum range if it is fired at an angle of
A 0° B 30°
C 45° D 60°
E 90° from the horizontal.
7. When ball having a projectile motion is rising,
A it decelerates.
B it accelerates. C it rises up with constant acceleration. D its acceleration becomes zero.
E none of the above
8. A stone is thrown in a vertical plane from a point at the edge of a cliff as shown in the following figure. After the stone has reached its maximum
height, it falls past the cliff edge to the beach.
The initial vertical component of the velocity of the stone is 10 ms-1. The
time taken between the stone passing the edge of the cliff on its way down and hitting the beach is 1.2 s.
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Ignoring air resistance, what is the height of the cliff measured from the beach?
A 5.06 m B 7.06 m C 12.00 m
D 19.06 m E 22.06 m
9. The greatest increase in the inertia of an object would be produced by
increasing the
A mass of the object from 1.0 kg to 2.0 kg B net force applied to the object from 1.0 N to 2.0 N C time that a net force is applied to the object from 1.0 s to 2.0 s
D speed of the object from 1.0 m/s to 2.0 m/s E none of the above
10. A small electric motor is 20% efficient. Its input power is 9.6 W when it is
lifting a mass of 0.5 kg at a steady speed v as shown below.
What is the value of v?
A 0.39 ms-1 B 2.0 ms-1 C 2.8 ms-1 D 3.0 ms-1 E 3.2 ms-1
11. A ball of mass 0.2 kg is attached to an inextensible string of negligible mass
and swung in a vertical circle of radius 0.2 m. If its speed at the top of its circular path is 2 ms-1, what is the tension in the string at that moment?
A 1.96 N
B 2.04 N C 4 N D 5.96 N
E 6 N
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12. A car of mass 800 kg decelerates from 22 ms-1 to rest in 12 s. At what average rate must the braking surfaces lose heat if their temperature is not
to rise significantly?
A 16.1 kW B 16.5 kW C 19.8 kW
D 21.3 kW E 24.2 kW
13. An object is pushed from rest in a horizontal straight line by a variable force
F on a rough ground. The ground exerts a constant frictional force of 5 N
throughout the motion of the object. The graph of how the variable force F
varies with displacement x is shown below.
The magnitude of the kinetic energy of the object when it has travelled 10 m is
A the area A
B the area A + B C the area A + C D the area A + B + C + D
E the area B + D + E
14. A mass is attached to a string and whirled in a vertical circle. The angular
velocity of the circular motion is gradually increased. At which point of the
motion is the string most likely to break and in which direction will the mass move immediately after the string breaks?
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The string is most likely to
break when the mass is at the The mass will move
A side where the mass is moving
up upwards
B top radially outwards
C top along the tangent to the
circular motion
D bottom radially outwards
E bottom along the tangent to the
circular motion
15. Potential energy and kinetic energy are types of
A electrical energy B magnetic energy
C thermal energy D mechanical energy E natural energy
16. Two identical blocks are released from rest from the tops of two ramps as
shown below.
Assuming no friction, what is the ratio of their speeds at the bottom if the
ratio of the length is 2, i.e., 2Y
X ?
A 1.12
B 1.86 C 2.26
D 3.50 E 5.52
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17. The speed of a vehicle of total mass 1.60 x 103 kg was brought down to 14.0 ms-1 on a level road by applying brakes. On braking, 550 kJ of heat
was produced. What is the speed of the vehicle just before the brakes were applied?
A 40.24 ms-1 B 29.72 ms-1
C 26.24 ms- D 22.26 ms-1
E 18.22 ms-1
18. The graph (not drawn to scale) shows the variation with time of the
momentum of a ball as it is kicked on a straight line.
Initially, the momentum is 5.0 kg ms-1 at time t = 1.0 x 10-3 s. At time t = 3.0 x 10-3 s the momentum is -5.5 kg ms-1.
What is the magnitude of the average force acting on the ball between times
t = 1.0 x 10-3 s and t = 3.0 x 10-3 s? A 0.25 kN
B 0.50 kN C 3.50 kN
D 5.25 kN E 7.25 kN
19. Two spheres of masses 1 kg and 2 kg, where the 1-kg sphere is moving to
the right and 2-kg sphere is moving to the left, are travelling on a smooth horizontal surface with speeds 2 ms-1 and 3 ms-1 respectively on a straight line. They collide head-on elastically, and the respective speeds immediately after their separation are v1f and v2f respectively.
Which of the following statements is correct for the quantities immediately
after the elastic collision?
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Magnitude and direction of fv1 Magnitude and direction of fv2
A 3
1ms-1 to the left
3
14ms-1 to the right
B 3
2ms-1 to the left
3
5ms-1 to the left
C 3
5ms-1 to the right
3
2ms-1 to the left
D 3
14ms-1 to the left
3
1ms-1 to the right
E None of the above None of the above
20. Assuming heat capacity of a 10 g of water to be 42 J⁄K, the heat required
to raise its temperature from 25 °C to 45 °C would be
A 84 J
B 462 J C 840 J D 4620 J
E 8400 J
21. A sound wave of frequency 400 Hz is travelling in air at a speed of 320 m s⁄ .
The difference in phase between two points on the wave 0.2 m apart in the
direction of travel is
A 𝜋 2⁄ rad
B 𝜋 3⁄ rad
C 𝜋 4⁄ rad
D 𝜋 5⁄ rad
E 𝜋 6⁄ rad
22. The frequency of the fundamental mode of transverse vibration of a stretched
wire 1000 mm long is 256 Hz. When the wire is shortened to 400 mm at the
same tension, the fundamental frequency is closest to:
A 102 Hz B 162 Hz C 312 Hz D 416 Hz E 640 Hz
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23. An organ pipe of effective length 0.68 m is closed at one end. Given that the
speed of sound in air is 340 m s⁄ , the two lowest resonant frequencies are
closest to:
A 125 Hz and 250 Hz B 125 Hz and 375 Hz C 250 Hz and 500 Hz D 250 Hz and 750 Hz E 500 Hz and 1000 Hz
24. Two uncharged metal spheres, #1 and #2 are mounted on insulating support rods. A third metal sphere #3, carrying a positive charge, is then placed near
#1. Now a copper wire is momentarily connected between #1 and #2 and then removed. Finally, sphere #3 is removed. In this final state
A spheres #1 and #2 are still uncharged.
B spheres #1 and #2 both carry positive charge. C spheres #1 and #2 both carry negative charge.
D sphere #1 carries positive charge and #2 carries negative charge. E sphere #1 carries negative charge and #2 carries positive charge.
25. Experimenter A uses a test charge 2𝑞0 and experimenter B uses a very small
test charge 𝑞0 to measure an electric field produced by stationary charges. Experimenter A finds a field that is
A greater than the field found by experimenter B. B less than the field found by experimenter B. C the same as the field found by experimenter B.
D either greater or less than the field found by experimenter B, depending on the amount of charge of the test charges.
E either greater or less than the field found by experimenter B, depending on the masses of the test charges.
26. Two isolated charges, −𝑄 and −2𝑄, are 2 cm apart. If 𝐹 is the magnitude of
the force acting on charge −2𝑄, what are the magnitude and direction of the
force acting on charge −𝑄?
A 𝐹 2⁄ , toward −2𝑄.
B 2𝐹, away from −2𝑄.
C 𝐹, toward −2𝑄.
D 𝐹, away from −2𝑄.
E 2𝐹, toward −2𝑄.
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27. A hollow metal sphere of radius 𝑅 is positively charged. Of the following
distances from the center of the sphere, which location will have the greatest electric field strength?
A 0. B 𝑅 2⁄ .
C 𝑅.
D 2𝑅. E None of the above because the field is of constant strength.
28. A point charge 𝑄 = −900 × 10−9 C and two unknown point charges, 𝑞1 and 𝑞2, are placed as shown. The electric field at the origin O, due to charges 𝑄, 𝑞1 and 𝑞2 is equal to zero. The unknown point charge 𝑞1 is closest to
A +55 × 10−9 C. B +95 × 10−9 C. C −95 × 10−9 C. D +140 × 10−9 C. E −140 × 10−9 C.
29. Two conducting spheres of different radii each has charge −𝑄. Which of the following occurs when the two spheres are connected with a conducting wire?
A No charge flows. B Negative charge flows from the larger sphere to the smaller sphere
until the electric field at the surface of each sphere is the same. C Negative charge flows from the larger sphere to the smaller sphere
until the electric potential of each sphere is the same.
D Negative charge flows from the smaller sphere to the larger sphere until the electric field at the surface of each sphere is the same.
E Negative charge flows from the smaller sphere to the larger sphere until the electric potential of each sphere is the same.
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30. A capacitor of capacitance 𝐶 is charged to a potential difference of 𝑉 while a
second capacitor of capacitance 2𝐶 is charged to a potential difference of 2𝑉.
A combined capacitor is then formed by connecting the two positive plates together and the two negative plates together. What happens to this system
of capacitors?
A Both charge and energy increase. B Both charge and energy decrease.
C Both charge and energy remain constant. D Energy decreases but charge remains constant.
E Charge increases but energy remains constant.
31. Two point charges, +4.0 𝜇C and −4.0 𝜇C are placed as shown in the diagram.
An additional charge of +2.0 𝜇C is placed at point 𝐴. The electric potential
energy of this system of charges is closest to:
A −486 × 10−3 J B −455 × 10−3 J C −264 × 10−3 J D +264 × 10−3 J E +486 × 10−3 J
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32. In the circuit shown, the emf of the battery is 𝜀 = 10.0 V and each of the seven
capacitors has capacitance 𝐶 = 10.0 𝜇C. The charge on capacitor 𝐶1 is closest
to:
A 20.0 𝜇C
B 40.0 𝜇C
C 50.0 𝜇C
D 60.0 𝜇C
E 100.0 𝜇C
33. The ideal battery in the figure shown below has emf 𝜀 = 6.0 V. Plot 1 in the
figure above gives the electric potential difference 𝑉 that can appear across
resistor 𝑅1 of the circuit versus the current 𝐼 in that resistor. The scale of the
𝑉 axis is set by 𝑉𝑠 = 18.0 V and the scale of the 𝐼 axis is set by 𝐼𝑠 = 3.00 mA.
Plots 2 and 3 are similar plots for resistors 𝑅2 and 𝑅3 respectively. The current
in resistor 𝑅1 is closest to:
A 0.55 mA.
B 0.82 mA.
C 1.36 mA.
D 4.0 mA.
E 6.0 mA.
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34. Given that 𝜀1 = 10 V, 𝜀2 = 20 V, 𝑅1 = 10 Ω, 𝑅2 = 20 Ω and 𝑅3 = 40 Ω, the power
delivered by the battery 𝜀1 is closest to:
A 2.5 W.
B 5.0 W.
C 10.0 W.
D 12.5 W.
E 20.0 W.
35. A velocity selector has an electric field of magnitude 2470 N C⁄ directed
vertically upward and a horizontal magnetic field. Positively charged particles,
travelling east at a speed of 6.50 × 103 m s⁄ , enter the velocity selector and
are able to pass completely through without being deflected. When a different
particle with an electric charge of −4.00 × 10−12 C enters the velocity selector
travelling east, the net force acting on it is 1.90 × 10−9 N pointing directly
upward. The speed of this particle is closest to:
A 2750 m s⁄
B 5250 m s⁄
C 7750 m s⁄
D 8750 m s⁄
E 9250 m s⁄
36. A small coil lies inside a large coil. The two coils are horizontal and concentric as shown. The large coil carries a constant clockwise current. The smaller coil is pulled perpendicular out of the plane of the paper. Which of the following
describes the direction of the induced current in the smaller coil and the resultant force between the coils?
A counter-clockwise, attraction.
B clockwise, attraction. C counter-clockwise, repulsion.
D clockwise, repulsion. E no induced current, no force.
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37. The circuit shown is in a uniform magnetic field that is into the page and is
decreasing in magnitude at a rate of 150 T s⁄ . Determine the reading on the
ammeter and the direction of current flowing through the ammeter.
A 0.35 A, downward.
B 0.35 A, upward.
C 0.50 A, upward.
D 0.65 A, upward.
E 0.65 A, downward.
38. A steady current 𝐼 dissipates a certain power in a variable resistor. The
resistance is remained to obtain the same power when a sinusoidal
alternating current is used. What is the r.m.s. value of the alternating current?
A 𝐼 2⁄
B 𝐼 √2⁄
C 𝐼
D √2 𝐼 E 2𝐼
39. A capacitor is connected in series to an ideal a.c. power supply. The voltage across the capacitor
A lags the current in the capacitor by 90∘. B leads the current in the capacitor by 90∘. C is in phase with the current in the capacitor.
D leads the current in the capacitor by 45∘. E lags the current in the capacitor by 45∘.
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40. The wavelength of light in water is 788 nm. If the refractive index for this
light in water is 1.33, the speed of this light in water is closest to:
A 2.95 × 108 m s−1 B 1.95 × 108 m s−1 C 1.25 × 108 m s−1 D 2.25 × 108 m s−1 E 2.50 × 108 m s−1
41. A ray of light propagates in water (𝑛 = 1.333) and strikes a sheet of glass
(𝑛 = 1.523). If the angle of refraction in the glass is 35.2∘, the angle of
incidence is closest to:
A 30.3∘ B 32.8∘ C 35.2∘ D 41.2∘ E 48.8∘
42. Two thin lenses are placed 5 cm apart along the same axis and illuminated
with a beam of light parallel to that axis. The first lens in the path of the
beam is a diverging lens of focal length 10 cm whereas the second is a
converging lens of focal length 5 cm. If the second lens is now moved towards
the first, the emergent light
A changes from parallel to divergent
B changes from divergent to parallel C changes from parallel to convergent D changes from convergent to parallel
E changes from convergent to divergent
43. Two identical light waves, A and B, are emitted from different sources and
meet at a point P. The distance from the source of A to the point P is 𝐿𝐴; and
the source of B is a distance 𝐿𝐵 from P. Which one of the following statements
is necessarily true concerning the interference of the two waves?
A A and B will interfere constructively because their amplitudes are the same.
B A and B will interfere destructively if 𝐿𝐴 = 𝐿𝐵.
C A and B will interfere destructively if 𝐿𝐴 − 𝐿𝐵 = (𝑚 + 1 2⁄ )𝜆 where
𝑚 = 0,1,2,3, …
D A and B will interfere destructively if 𝐿𝐴 is not equal to 𝐿𝐵.
E A and B will interfere constructively because their wavelengths are the same.
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44. Diffraction occurs when light passes through a single slit. Rank the following three choices in decreasing order, according to the extent of the diffraction
that occurs (largest diffraction first):
I – blue light, wide slit
II – red light, narrow slit
III – red light, wide slit
Note: The blue light referred to in choices I and III is the same wavelength.
Also, the narrow slit referred to in choices I and II is the same width.
A I, II, III
B II, I, III C II, III, I D I, III, II
E III, II, I
45. A grating spectrometer is used to view the spectrum of light from a helium discharge tube. The three brightest spectral lines seen are blue, red and
yellow in colour. These lines appear at the positions labeled A, B and C in the figure below though not necessarily in that order of colour. In this
spectrometer, the distance between the grating and screen is 30 cm and the
slit spacing in the grating is 1870 nm.
The wavelength of the red colour spectral line is closest to:
A 398 nm
B 454 nm
C 565 nm
D 669 nm
E 767 nm
46. Arrange the following electromagnetic waves in order of increasing energy:
visible light, X-rays, microwaves, infra-red and ultra-violet.
A X-rays, ultra-violet, visible light, infra-red and microwaves.
B X-rays, infra-red, visible light, ultra-violet and microwaves. C Visible light, infra-red, ultra-violet, microwaves and X-rays.
D Microwaves, infra-red, visible light, ultra-violet and X-rays. E Microwaves, ultra-violet, infra-red, X-rays and visible light.
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47. Electrons are emitted from a certain metal with a maximum kinetic energy of
2 eV when 6-eV photons are incident on its surface. If photons of half the
wavelength are incident on this metal which one of the following statements is true?
A No electrons will be emitted.
B Electrons will be emitted with a maximum kinetic energy of 2 eV.
C Electrons will be emitted with a maximum kinetic energy of 4 eV.
D Electrons will be emitted with a maximum kinetic energy of 8 eV.
E Electrons will be emitted with a maximum kinetic energy of 12 eV.
48. The de Broglie wavelength of an electron is 1.2 × 10−10 m. The magnitude of
momentum of the electron is closest to:
A 5.9 × 10−25 kg m s−1 B 1.8 × 10−24 kg m s−1 C 5.6 × 10−24 kg m s−1 D 1.7 × 10−23 kg m s−1 E 5.2 × 10−23 kg m s−1
49. Astronomers observe a series of spectral lines in the light from a distant
galaxy. On the hypothesis that the lines form the Lyman series for an (new?) unknown atom, they start to construct the energy-level diagram shown,
which gives the wavelengths of the first four lines and the short-wavelength limit of this series.
The energy of the ground state is closest to:
A −8.18 eV B −6.14 eV
C 0 eV
D +6.14 eV
E +8.18 eV
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50. The radioactive isotope radon-222 ( Rn86222 ) may decay spontaneously by
emitting an alpha particle. The daughter nucleus is an isotope of polonium
(Po). The atomic masses of these isotopes are:
Rn222 , 222.0157 u; Po, 218.00896 u; He4 , 4.00260 u;
A sample of radon-222 contains 3.0 × 107 nuclei. The total energy that will be
release in a time interval of 3𝑇1 2⁄ through alpha decay of the radon-222 is
closest to:
A 3.856 MeV
B 5.785 × 107 MeV
C 8.677 × 107 MeV
D 1.012 × 108 MeV
E 1.085 × 108 MeV
END OF PAPER