Phy Mock P1a
Phy Mock P1a
GENERAL INSTRUCTIONS
(1) There are TWO sections, A and B, in this Paper. You are advised to finish Section A in about 50 minutes.
(2)    Section A consists of multiple-choice questions in this question paper, while Section B contains
       conventional questions printed separately in Question-Answer Book B.
(3)    Answers to Section A should be marked on the Multiple-choice Answer Sheet while answers to Section B
       should be written in the spaces provided in the Question-Answer Book. The Answer Sheet for Section A
       and the Question-Answer Book for Section B will be collected separately at the end of the
       examination.
(4) The diagrams in this paper are NOT necessarily drawn to scale.
(5)    The last two pages of this question paper contain a list of data, formulae and relationships which you may
       find useful.
(2)    When told to open this book, you should check that all the questions are there. Look for the words ‘END
       OF SECTION A’ after the last question.
(4)    ANSWER ALL QUESTIONS. You are advised to use an HB pencil to mark all the answers on the
       Answer Sheet, so that wrong marks can be completely erased with a rubber. You must mark the answers
       clearly; otherwise you will lose marks if the answers cannot be captured.
(5)    You should mark only ONE answer for each question. If you mark more than one answer, you will receive
       NO MARKS for that question.
1 Some hot coffee spills out of a cup onto the floor on a cold sunny day.
                                   Temperature / C           Length / cm
                                             25                    7.8
                                            100                   15.9
       Assume that the length of the liquid column increases linearly with the temperture. What is the
       increase in length of the liquid column when the temperature increases by 10 C?
       A      0.8 cm
       B      1.1 cm
       C      1.6 cm
       D      3.1 cm
state X state Y
capillary tube
liquid thread
                     air column
                                                                 hot water
                 water at room                                   bath
                 temperature
4      A ball is dropped vertically onto an inclined plane. When it collides with the plane, the force
       acting on it by the plane is perpendicular to the plane. Which of the following arrows give(s) the
       possible direction(s) of motion of the ball just after the collision?
                                                                ball
                                                        R
       A      P only
       B      Q only
       C      P, Q and R
       D      None of them
6      Trolley X moves on a horizontal smooth surface and collides head on with stationary trolley Y.
       Both trolleys are of the same mass.
trolley X trolley Y
       If the collision is elastic, how will the trolleys move after the collision?
       A      The trolleys will move in opposite direction at the same speed.
       B      The trolleys will move in opposite direction at different speeds.
       C      X will stop and Y will move away from X.
       D      Y will remain stationary and X will move away from Y.
pulling force
table
       Which of the following pairs of forces DO NOT have the same magnitude?
       (1)     The pulling force and the friction acting on the block
       (2)     The pulling force and the resultant force acting on the block by the table
       (3)     The weight of the block and the normal force acting on the block by the table
       A      (1) only
       B      (2) only
       C      (1) and (2) only
       D      (1), (2) and (3)
8      The following ornament is hung from the ceiling for Christmas decoration. It consists of metal
       chains and plastic balls.
       A pair of angel wings are then attached to the ball in the middle as shown. Which of the
       following statements about the tensions in the chains is correct? Let TX, TY and TZ be the
       tensions in chains X, Y and Z respectively.
       A      TX, TY and TZ are equal before the wings are attached.
       B      TX becomes larger after the wings are attached.
       C      TY is larger than TX after the wings are attached.
       D      TZ becomes larger after the wings are attached.
car P
                                         car Q
                                                                            t3
                        0                                                             time
                                    t1                  t2                       t4
       At which instant(s) does car P meet car Q? At which instant(s) does car P return to position X?
                       Meet car Q                 Return to position X
       A              At t1, t2 and t3                       At t2 and t4
       B              At t1, t2 and t3                            At t4
       C               At t2 and t4                          At t2 and t4
       D               At t2 and t4                               At t4
*10 The gravitational field strength at a distance d from the Earth’s surface is 8.8 N kg1. What is
       the gravitational field strength at a distance 2d from the Earth’s surface? Assume the effect of
       the Sun and other planets is negligible. The radius of the Earth is 6370 km.
       A      5.77 N kg1
       B      7.79 N kg1
       C      7.94 N kg1
       D      17.6 N kg1
                     ball X
                                      track
       A student modifies the track as shown below. Its upper end remains at the same height. He then
       releases ball Y from the upper end. Ball Y flies freely after leaving the track. Balls X and Y are
       of the same mass.
               ball Y
                                 modified track
cargo
pushing force
       Which of the following factors determine(s) the size of F? Assume the cargo does not slide on
       the ground.
       (1)     The height of the centre of gravity of the cargo
       (2)     The height of the position where the pushing force acts on
       (3)     The weight of the cargo
       A      (2) only
       B      (1) and (3) only
       C      (2) and (3) only
       D      (1), (2) and (3)
13     A train is moving along a straight horizontal track. A student on the train holds a cardboard with
       the long edge parallel to the horizontal. A metal ball is attached to the top edge via a string.
       During a certain period of time, the ball stays steadily at the position as shown below.
                       cardboard
                                                                string
metal ball
28
                   incident ray
                                                               
emergent ray
glass blobk
       Find , which is the angle that the ray bends after passing through the glass block. The
       refractive index of glass is 1.5.
       A      8.5
       B      16.8
       C      19.5
       D      44.8
15     The figure shows a snapshot of a section of a transverse wave travellling towards the right at
       time t = 0. The period of the wave is T.
direction of travel
                                                    P
                                                         R
                                                X
                                                               S
                                     E       F    G     H       I       J   K   L       M
              equilibrium
              position
                                         E       F GH       I       J       K       L       M
                   at t = 0
5 cm
20     When a beam of red light and a beam of violet light are incident on a diffraction grating, the
       two colours of light form maxima at different angles. Which of the following explains this?
       A      The red light and violet light are diffracted by different amounts as their wavelengths are
              different.
       B      The red light shows constructive interference at angles different from the violet light as
              their wavelengths are different.
       C      The red light and violet light are diffracted by different amounts as their speeds are
              slightly different.
       D      The red light shows constructive interference at angles different from the violet light as
              their speeds are slightly different.
circular wave
               straight wave
                                  barrier                                               barrier
                      incident
                      direction
       In which of the following circuits can the cell(s) last longer than the above one? Assume that all
       the cells are identical and all the light bulbs are identical and have fixed resistance.
       (1)
(2)
(3)
       A      (1) only
       B      (2) only
       C      (1) and (2) only
       D      (2) and (3) only
       Which of the following statements about a charged particle P placed between the two charges
       MUST BE correct?
       (1)    When P is placed on the line connecting the two charges, it experiences a larger force at
              places closer to one of the charges than in the middle between the charges.
       (2)    When P is placed at X, it does not experience any electrostatic force.
       (3)    When P is placed at Y, it experiences an electrostatic force towards the left.
       A      (1) only
       B      (2) only
       C      (1) and (3) only
       D      (1), (2) and (3)
25
a 4
                                                                 3
                                       6                             2
b 1
       The above network is connected to the other parts of circuit at terminals a and b. The voltage
       across a and b is 6 V. What is the current passing through the 1- resistor?
       A      1.5 A
       B      2A
       C      3A
       D      6A
M N
8 cm
       Find angle  that the string suspending M makes with the vertical.
       A      3.3
       B      8.2
       C      11.4
       D      19.7
*27 A charged particle enters a uniform magnetic field of 1.5  106 T at 6.3  105 m s1 and leaves
       the field after 0.01 s. The particle moves in a circular arc within the magnetie field, as shown in
       the figure below.
charged particle
       The charge of the particle is 3.2  1019 C and its mass is 3.4  1027 kg. Find the angular
       displacement  of the particle in passing the field.
       A      0.2 rad
       B      0.8 rad
       C      1.1 rad
       D      1.4 rad
29     The figure below shows the schematic diagram of an electric heater with metal case. The heater
       has a faulty design.
                                                             Y   heating element
                                                        X
                          live
neutral
                        earth
                                                                           metal case
       What problem(s) will arise if points X and Y are short-circuited during the operation of the
       heater?
       (1)    The fuse will not blow.
       (2)    The current will not be led to the ground via the earth wire.
       (3)    If a person touches the metal case, most current will flow through his body instead of the
              earth wire.
       A      (1) only
       B      (3) only
       C      (1) and (3) only
       D      (1), (2) and (3)
*30 When a fixed resistor is connected to a sinusoidal a.c. with a peak voltage V, it produces heat at
       a mean rate P. If the resistor is connected to a d.c. power supply of a constant voltage V, what is
       the mean rate of heat production?
       A      P
       B          2P
       C      2P
       D      4P
*32 One gram of uranium-235 undergoes the following fission reaction to produce energy.
               235
                92 U   + 01 n  144      90        1
                                 56 Ba + 36 Kr + 2 0 n
                           235
       Given: mass of       92 U   = 235.043 923 u
                           144
                mass of     56 Ba   = 143.922 955 u
                           90
                mass of    36 Kr =   89.919 528 u
END OF SECTION A
              1                                                       l
A4.    pV =     Nm c 2     kinetic theory equation        D4.    R=                resistance and resistivity
              3                                                         A
              3RT
A5.    EK =                molecular kinetic energy       D5.    R = R1 + R2       resistors in series
              2N A
                                                                 1   1   1
                                                          D6.      =   +           resistors in parallel
                                                                 R R1 R 2
               v p
B1.    F =m      =         force                          D7.    P = IV = I2R      power in a circuit
               t t
                                                                                   force on a moving charge in a
B2.    moment = F  d      moment of a force              D8.    F = BQv sin 
                                                                                   magnetic field
                           gravitational potential                                 force on a current-carrying
B3.    EP = mgh                                           D9.    F = BIl sin 
                           energy                                                  conductor in a magnetic field
              1                                                       0 I         magnetic field due to a long
B4.    EK =     mv 2       kinetic energy                 D10.   B=
              2                                                       2 πr         straight wire
            v2                                                              
B6.    a=      = 2r       centripetal acceleration       D12.   =N               induced e.m.f.
             r                                                              t
              λD           fringe width in
C1.    y =                                               E1.    N = N0ekt        law of radioactive decay
               a           double-slit interference
                           diffraction grating                          ln 2
C2.    d sin  = n                                       E2.    t1 =              half-life and decay constant
                           equation                               2
                                                                         k