Mock Exam 2013 Paper 1A

NEW SENIOR SECONDARY PHYSICS AT WORK

MOCK EXAMINATION 2014 PHYSICS PAPER 1

Time allowed: 2 hours 30 minutes This paper must be answered in English

GENERAL INSTRUCTIONS

(1) There are TWO sections, A and B, in this Paper. You are advised to finish Section A in about 60 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.

INSTRUCTIONS FOR SECTION A (MULTIPLE-CHOICE QUESTIONS)

(1) Read carefully the instructions on the Answer Sheet. After the announcement of the start of the examination, you should first insert the information required in the spaces provided. No extra time will be given after the ‘Time is up’ announcement.

(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.

(3) All questions carry equal marks.

(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.

(6) No marks will be deducted for wrong answers.

Mock Exam Paper 1A 1 Section A

There are 33 questions. Questions marked with * involve knowledge of the extension component.

1 John measures the energy needed to raise the temperature of various amounts of water by 10 C. The figure below shows his results. According to John’s result, what is the specific heat capacity of water?

energy / kJ

0 0.1 0.2 0.3 0.4 0.5 mass / kg

A 4000 J kg–1 C–1 B 4200 J kg–1 C–1 C 4400 J kg–1 C–1 D 5400 J kg–1 C–1

2 Susan wipes the surface of a can of soft drink of mass 300 g using a piece of wet cloth. Both the soft drink and the wet cloth are at room temperature. Then she places the soft drink in front of a fan which blows wind on the can. After a while, the temperature of the soft drink decreases by 5 C. Assume that the water takes energy only from the soft drink to evaporate. Find the mass of water evaporated. Specific heat capacity of the soft drink = 3700 J kg–1 C–1 Specific heat capacity of the water = 4200 J kg–1 C–1 Specific latent heat of vaporization of water = 2.26  106 J kg–1 A 2.13 g B 2.16 g C 2.38 g D 2.46 g

Mock Exam Paper 1A 2 3 A small amount of crushed ice at 0 C is put into a large cup of cold water at 0 C. Which of the following statements is correct? Assume there is no heat transfer between the water and the surroundings. A The temperature of the water will not change. B The total internal energy of the cup of water is unchanged after crushed ice is added to the water. C The total mass of ice in the cup will drop because the crushed ice has a much smaller internal energy than the water in the cup. D The total mass of ice in the cup will increase.

*4 A student is studying the relationship between the pressure and the volume of air at constant temperature using a syringe and a pressure sensor as shown. Which of the following is the most effective way to minimize the temperature change of the air?

syringe pressure sensor

A Pushing the piston quickly. B Pushing the piston slowly. C Using a smaller syringe D Wrapping the syringe with insulating material

5 Richard stands on a weighing scale graduated in kilograms in a lift. When the lift accelerates upwards at 1.5 m s2, the scale reads 68 kg. What is Richard’s mass? (g = 9.81 m s–2) A 59 kg B 62 kg C 68 kg D 80 kg

Mock Exam Paper 1A 3 Go on to the next page 6 A car travels along a straight road. The figure below shows its accelerationtime graph, taking its moving direction as positive.

acceleration / m s2

0 time / s 10 16 1

If the car’s velocity is 54 km h1 at t = 0, which of the following statements is/are correct? (1) The car’s velocity is 68 km h1 at t = 16 s. (2) The car’s average acceleration in these 16 seconds is 0.875 m s2. (3) The car changes its moving direction at t = 10 s. A (1) only B (2) only C (1) and (3) only D (1), (2) and (3)

7 Three blocks X, Y and Z are connected by light inextensible strings and X is held stationary as

shown below. T1 and T2 are two tensions in the strings.

Then the blocks are released and fall freely. Which of the following correctly shows the

relationship between T1 and T2 when the blocks are stationary and falling freely? Stationary Falling freely

A T2 = T1 T2 > T1

B T2 = T1 T2 = T1

C T2 > T1 T2 > T1

D T2 > T1 T2 = T1

Mock Exam Paper 1A 4 8 A boy slides down a slide at a constant speed as shown. The slide is supported at two points X and Y.

How do the reaction forces acting on the slide at X and Y change as the boy slides down? X Y A increases decreases B increases increases C decreases decreases D decreases increases

9 A girl stands on a stationary skateboard. Then she starts to walk forwards on the skateboard as shown. Neglect the friction between the skateboard and the ground.

Which of the following statements is correct? A The girl remains at the same position and the skateboard moves backwards. B The girl moves forwards and the skateboard moves backwards. C The girl moves forwards and the skateboard remains at the same position. D Both the girl and the skateboard move forwards.

Mock Exam Paper 1A 5 Go on to the next page 10 Edward and Fred are driving their own cars. Edward’s car has a larger mass than Fred’s. The two cars collide head on with each other. Edward and Fred have the same mass and the same time of impact. Which of the following statements must be correct? (1) The impact forces acting on Edward and Fred have the same magnitude. (2) The impact forces acting on the two cars have the same magnitude. (3) The changes in velocity of the two cars have the same magnitude. A (2) only B (3) only C (1) and (2) only D (1), (2) and (3)

*11 An object is projected horizontally with a speed v from a cliff as shown.

cliff level X

level Y

Which of the following statements is/are correct? (1) If the initial speed of the object is increased to 2v, the time needed for it to travel from level X to level Y will be halved. (2) If the initial speed of the object is increased to 2v, the horizontal distance it travels when it falls from level X to level Y will be doubled. (3) If the mass of the object is doubled, the time needed for it to travel from level X to level Y will be halved. A (2) only B (1) and (2) only C (1) and (3) only D (1), (2) and (3)

Mock Exam Paper 1A 6 12 A ping-pong ball is thrown vertically upwards with an initial speed u. It then falls back to the initial position. Air resistance is NOT negligible. Which of the following statements is/are correct? (1) The ball’s speed is lower than u when the ball returns to its initial position. (2) The total energy of the ball and the air is conserved. (3) The net force acting on the ball is zero when the ball reaches its highest position. A (1) only B (3) only C (1) and (2) only D (1), (2) and (3)

*13 Two identical balls are suspended by strings from the two ends of a horizontal rod. Each string is 10 cm long and the rod is 20 cm long. When the rod rotates about its centre at an angular speed of , both strings make an angle of 30 with the vertical. Find . (g = 9.81 m s–2) 

20 cm 10 cm 10 cm 30 30

ball ball A 0.92 rad s1 B 1.19 rad s1 C 4.76 rad s1 D 6.14 rad s1

14 Two coherent sources X and Y produce circular water waves in a ripple tank. P is a point where constructive interference occurs. Which of the following statements about point P must be incorrect? (1) A trough from X meets a trough from Y at P at some instants. (2) The particle at P is at its equilibrium position at some instants. (3) The particle at P always stays at the maximum displacement. A (1) only B (2) only C (3) only D (1) and (2) only

Mock Exam Paper 1A 7 Go on to the next page 15 The figure shows a stationary wave formed on a string fixed at both ends. At the moment shown, point X on the stationary wave is moving upwards.

Which of the following statements is/are correct? (1) Point Y is momentarily at rest at the moment shown. (2) The wavelength of the wave is 1 m. (3) The average speeds of points X and Y in one period’s time are the same. A (1) only B (2) only C (1) and (2) only D (2) and (3) only

*16 A lens is placed in front of an object. The focal length of the lens is 12 cm. A virtual image is formed at a distance of 10 cm from the lens. Which of the following lenses is used and what is the object distance? Type of lens Object distance A concave 5.5 cm B concave 60 cm C convex 5.5 cm D convex 60 cm

17 A beam of monochromatic light travels from air into water. How do the speed and the wavelength of the light change? Speed Wavelength A remains unchanged remains unchanged B decreases remains unchanged C decreases decreases D decreases increases

Mock Exam Paper 1A 8 *18 A monochromatic light ray is directed onto a plane transmission grating and the 2nd-order bright fringe is produced at 43. What is the maximum order of bright fringe produced?

A 2 B 3 C 4 D 5

19 Three musical notes X, Y and Z are displayed on a CRO screen as shown. The CRO settings for them are the same.

Note X:

Note Y:

Note Z:

Which of the following statements about the notes is/are correct? (1) Note X is louder than note Z. (2) Note X has a lower pitch than note Y. (3) Notes X and Z have different qualities. A (2) only B (3) only C (1) and (3) only D (2) and (3) only

Mock Exam Paper 1A 9 Go on to the next page

air 55 20 medium X

A ray of monochromatic light enters a solid transparent medium X from air. The incident ray makes an angle of 55 with the boundary plane as shown. Which of the following statements is/are correct? (1) The higher the speed of light in medium X, the smaller the angle of refraction. (2) The angle of refraction must be smaller than 35. (3) Dispersion of light will occur in medium X. A (1) only B (2) only C (1) and (2) only D (1) and (3) only

(For Q2122.) A longitudinal wave travels past a series of particles on a spring from left to right with a speed of 40 cm s1. The figure below shows the equilibrium positions of the particles and their positions at time instant t.

equilibrium positions

time t

21 Which of the following particles is momentarily at rest at time instant t? A Particle E B Particle F C Particle G D Particle H

22 What is the period of the longitudinal wave? A 0.5 s B 1.0 s C 2.0 s D Cannot be determined

Mock Exam Paper 1A 10 X Y 23 +2 µC –3 µC

Two small conducting spheres X and Y carrying charges +2 µC and –3 µC respectively are situated at fixed positions as shown. A positive test charge q is located somewhere on the line joining the centres of the spheres. The resultant electrostatic force due to the spheres acting on q points towards the left. After the spheres have touched each other momentarily and returned to their original positions, the resultant electrostatic force on q points towards the right. Where is/are the possible location(s) of the test charge q? (1) To the left of X (2) To the right of Y (3) Between the spheres A (1) only B (2) only C (3) only D (1) and (2) only

24 Two identical light bulbs P and Q, each rated at ‘6 V, 6 W’, are connected to a 12-V power supply as shown. The range of the variable resistor is 0–18 . The power source has negligible internal resistance. Which of the following statements is/are correct? 12 V

(1) When the variable resistor has zero resistance, bulbs P and Q work at the rated power. (2) When the variable resistor is at its maximum resistance, bulb Q has the maximum brightness. (3) Bulb P is always brighter than bulb Q. A (1) only B (3) only C (1) and (3) only D (2) and (3) only

25 Light bulbs X and Y are connected in series to a power supply. X is rated at ‘12 V, 24 W’ and Y at ‘6 V, 18 W’. If both bulbs work within their rated power, what is the maximum voltage output from the power supply?

Mock Exam Paper 1A 11 Go on to the next page A 6 V B 12 V C 14 V D 16 V

*26 A particle of mass m and charge +2e is accelerated between two parallel charged plates X and Y. It leaves X at speed v and reaches Y at speed 3v as shown. What is the potential difference V across the plates?

X Y mv2 A 2e mv2 B e 2mv2 C e 9mv2 D 4e

27 Q P

In the above figure, P and Q are two metal spheres suspended from two insulating strings of equal length. Which of the following statements is/are correct? (1) P and Q carry opposite charges. (2) Q must carry a larger net charge than P. (3) P and Q are of different mass. A (2) only B (3) only C (1) and (3) only D (2) and (3) only *28 Which of the following statements about the Hall effect is INCORRECT? A The sign of the Hall voltage depends on the charge carrier density of a conductor.

Mock Exam Paper 1A 12 B The Hall voltage on a current-carrying conductor depends on the material that makes the conductor. C The Hall effect can be applied to measure the magnitude of a steady magnetic field. D When we use a Hall probe to measure a magnetic field, we need to vary the orientation of the probe head.

29 A metal rod XY is placed on two smooth parallel conducting rails whose ends P and Q are connected by a conducting wire. The rails are tilted slightly so that the rod slides to the right into a uniform magnetic field pointing out of the paper as shown. Which of the following statements is/are correct when the rod is moving in the magnetic field?

conducting wire

conducting rails uniform magnetic field

(1) A current passes from P to Q through the wire. (2) There will be no potential difference across X and Y if the conducting wire is broken. (3) The rod will slide to the right at a higher rate if the wire connecting P and Q is removed. A (1) only B (3) only C (2) and (3) only D (1), (2) and (3)

*30 An electrical appliance rated at ‘12 V, 25 W’ is connected to the 220-V mains through a step-down transformer. The output voltage of the transformer is 12 V. The efficiency of the transformer is 90%. Find the current drawn from the mains. A 114 mA B 120 mA C 126 mA D 140 mA

Mock Exam Paper 1A 13 Go on to the next page 31 A radioactive source with a half-life of 10 hours is placed in front of a G-M tube. The count rate measured by the G-M tube is x counts per minute. Estimate the measured count rate after 20 hours. Assume the background count rate is 40 counts per minute. 1 A x  20 counts per minute 2 1 B x  20 counts per minute 2 1 C x  40 counts per minute 4 1 D x  30 counts per minute 4

32 Which of the following statements about radiation safety is/are correct? (1) The unit of absorbed dose of ionizing radiation is sievert. (2) Radon is one of the major sources of background radiation. (3)  radiation cannot cause much harm to our body because it can be stopped by skin. A (1) only B (2) only C (3) only D (1) and (2) only

33 A thorium nuclide undergoes the following decays and becomes Z. 232 α β β 90 Th  X  Y  Z Which of the following statements is/are correct?

232 (1) 90 Th and Z are isotopes. (2) X has more protons than Y. (3) Y has more neutrons than Z. A (1) only B (2) only C (1) and (3) only D (1), (2) and (3)

END OF SECTION A

Mock Exam 2014 Paper 1A 14 List of data, formulae and relationships Data molar gas constant R = 8.31 J mol1 K1 23 1 Avogadro constant NA = 6.02  10 mol acceleration due to gravity g = 9.81 m s2 (close to the Earth) universal gravitational constant G = 6.67  1011 N m2 kg2 speed of light in vacuum c = 3.00  108 m s1 charge of electron e = 1.60  1019 C 31 electron rest mass me = 9.11  10 kg 12 2 1 2 permittivity of free space 0 = 8.85  10 C N m 7 1 permeability of free space 0 = 4  10 H m atomic mass unit u = 1.661  1027 kg (1 u is equivalent to 931 MeV) astronomical unit AU = 1.50  1011 m light year ly = 9.46  1015 m parsec pc = 3.09  1016 m = 3.26 ly = 206 265 AU Stefan constant  = 5.67  108 W m2 K4 Planck constant h = 6.63  1034 J s

Rectilinear motion Mathematics For uniformly accelerated motion: Equation of a straight line y = mx + c Arc length = r v = u + at 1 Surface area of cylinder = 2rh + 2r2 s = ut + at 2 2 Volume of cylinder = r2h v2 = u2 + 2as Surface area of sphere = 4r2 4 Volume of sphere = πr 3 3 For small angles, sin   tan    (in radians) Astronomy and Space Science Energy and Use of Energy GMm  U =  gravitational potential energy E  illuminance r A P = AT4 Stefan’s law Q A(T T ) = H C rate of energy transfer by conduction f v λ t d   Doppler effect f c λ  0 0 U = thermal transmittance U-value d 1 P = Av3 maximum power by wind turbine 2 Atomic World Medical Physics 1 1.22λ m v 2 = hf   Einstein’s photoelectric equation   Rayleigh criterion (resolving power) 2 e max d 1  m e4  13.6 1 E =  e =  eV power = power of a lens n 2  2 2  2 f n 8h  0  n energy level equation for hydrogen I L =10log intensity level (dB) atom I0 h h Z = c acoustic impedance  = = de Broglie formula 2 p mv I r (Z  Z )  = = 2 1 intensity reflection coefficient 1.22λ I (Z  Z )2   Rayleigh criterion (resolving power) 0 2 1 d x I  I0e transmitted intensity through a

15 medium energy transfer during Q1Q2 A1. E = mcT D1. F = 2 Coulomb’s law heating and cooling 4π 0 r

energy transfer during Q electric field strength due to a A2. E = lm D2. E = 2 change of state 4π 0 r point charge

equation of state for an Q electric potential due to a A3. pV = nRT D3. V = ideal gas 4π 0 r point charge

1 V electric field between parallel A4. pV = Nmc 2 kinetic theory equation D4. E = 3 d plates (numerically) 3RT A5. EK = molecular kinetic energy D5. I = nAvQ general current flow equation 2N A l D6. R = resistance and resistivity A v p B1. F = m = force D7. R = R1 + R2 resistors in series t t

1 1 1 B2. moment = F  d moment of a force D8. = + resistors in parallel R R1 R2 gravitational potential B3. E = mgh D9. P = IV = I2R power in a circuit P energy

1 2 force on a moving charge in a B4. EK = mv kinetic energy D10. F = BQv sin  2 magnetic field force on a current-carrying B5. P = Fv mechanical power D11. F = BIl sin  conductor in a magnetic field

v2 BI B6. a = = 2r centripetal acceleration D12. V = Hall voltage r nQt

Gm m Newton’s law of  I magnetic field due to a long B7. F = 1 2 D13. B = 0 r 2 gravitation 2πr straight wire

 NI magnetic field inside a long D14. B = 0 l solenoid

λD fringe width in  C1. y = D15.  = N induced e.m.f. a double-slit interference t ratio of secondary voltage to diffraction grating Vs N s C2. d sin  = n D16.  primary voltage in a equation V N p p transformer

1 1 1 equation for a single C3.  = u v f lens

kt E1. N = N0e law of radioactive decay

t ln 2 E2. 1 = half-life and decay constant 2 k activity and the number of E3. A = kN undecayed nuclei

E4. E = mc2 mass-energy relationship

Mock Exam Paper 1A 16