Cambridge IGCSE Physics 0625 — 2007 Oct/Nov Paper 2 · Variant 1

This document consists of 16 printed pages. SP (MML 13331 4/06) T25940/5 © UCLES 2007 [Turn over UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education PHYSICS 0625/02 Paper 2 Core October/November 2007 1 hour 15 minutes Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your Centre number, candidate number and name on all the work you hand in. Write in dark blue or black pen. You may use a soft pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. DO NOT WRITE IN ANY BARCODES. Answer all questions. You may lose marks if you do not show your working or if you do not use appropriate units. Take the weight of 1 kg to be 10 N (i.e. acceleration of free fall = 10 m/s2). At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. For Examiner’s Use 1 2 3 4 5 6 7 8 9 10 11 12 Total * 8 9 0 2 3 2 5 1 1 3 * www.XtremePapers.com

2 0625/02/O/N/07 For Examiner’s Use © UCLES 2007 1 Fig. 1.1 shows some liquid in a measuring cylinder. The metal can next to it has a cross- sectional area which is four times that of the measuring cylinder. cm3 100 90 80 70 60 50 40 30 20 10 metal can measuring cylinder liquid Fig. 1.1 (a) State the volume of the liquid. volume = … cm3 [1] (b) The liquid is poured into the metal can. On Fig. 1.1, draw the surface of the liquid in the can. [2] (c) Complete the following sentence. The pressure of the water at the bottom of the can is ……………………………… than the pressure that the water had at the bottom of the measuring cylinder. [1] [Total: 4]

3 0625/02/O/N/07 [Turn over For Examiner’s Use © UCLES 2007 2 A theatre measures 100 m × 80 m × 25 m. The air inside it has a density of 1.3 kg / m3 when it is cool. (a) Calculate the volume of the air in the theatre. volume of air = … m3 [1] (b) Calculate the mass of the air. State the equation you are using. mass of air = … [4] (c) Some time after the doors are opened, the heating in the theatre is switched on. State and explain what happens to the mass of the air in the theatre as it warms up. statement … … explanation … … [2] (d) Suggest why the temperature of the air in the balcony of the theatre (nearer the ceiling) is likely to be greater than that lower down in the theatre. … [1] [Total: 8]

4 0625/02/O/N/07 For Examiner’s Use © UCLES 2007 3 Fig. 3.1 shows a simple mercury barometer, drawn 1/10 full size. glass tube mercury reservoir Fig. 3.1 (a) On Fig. 3.1, use your rule to make an appropriate measurement, and then use it to calculate the atmospheric pressure. atmospheric pressure = … cm Hg [2] (b) State what occupies the space in the tube above the mercury. … … [1]

5 0625/02/O/N/07 [Turn over For Examiner’s Use © UCLES 2007 (c) On another occasion, the atmospheric pressure is much less than that shown in Fig. 3.1. On Fig. 3.1, mark where the mercury surfaces in the tube and in the reservoir might be. [2] (d) The tube above the mercury gets broken and allows air to move in to and out of the tube. Explain why the barometer no longer functions. … … [2] [Total: 7]

6 0625/02/O/N/07 For Examiner’s Use © UCLES 2007 4 A diesel engine is used to drag a boat up a slipway (see Fig. 4.1). diesel engine slipway s h Fig. 4.1 The boat finishes in the position shown by the broken outline. (a) On Fig. 4.1, carefully mark (i) the weight W of the boat, using an arrow labelled W, [1] (ii) the friction force F on the boat, using an arrow labelled F. [1] (b) State, in terms of W, F, h and s, how you could calculate (i) the work done lifting the weight of the boat, … … [1] (ii) the work done against the friction force, … … [1] (iii) the total work done pulling the boat up the slipway. … [1] (c) What other measurement would you need to make if you wanted to calculate the useful power output of the diesel engine? … [1] [Total: 6]

7 0625/02/O/N/07 [Turn over For Examiner’s Use © UCLES 2007 5 Fig. 5.1 shows a liquid-in-glass thermometer. –10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 capillary tube liquid Fig. 5.1 (a) The thermometer is used for measuring temperatures in school laboratory experiments. State the units in which the temperatures are measured. … [1] (b) On Fig. 5.1, mark where the liquid thread will reach when the thermometer is placed in (i) pure melting ice (label this point ICE), [1] (ii) steam above boiling water (label this point STEAM). [1] (c) A liquid-in-glass thermometer makes use of the expansion of a liquid to measure temperature. Other thermometers make use of other properties that vary with temperature. In the table below, write in two properties, other than expansion of a liquid, that can be used to measure temperature. example expansion OF a liquid 1. OF 2. OF [2] [Total: 5]

8 0625/02/O/N/07 For Examiner’s Use © UCLES 2007 6 A motorcyclist drives along a straight road. Fig. 6.1 gives information about the first 10 s of his ride. start 0 m / s after 5 s 9 m / s after 10 s 18 m / s Fig. 6.1 (a) From the information on Fig. 6.1, (i) describe the motion of the motorcyclist by ticking one of the following boxes, constant speed uniform acceleration uniform deceleration [1] (ii) estimate the average speed of the motorcyclist during the 10 s, average speed = … m / s [1] (iii) calculate the distance travelled during the 10 s. distance travelled = … m [2] (b) State why the distance travelled in the first 5 s is less than half of the distance travelled in the first 10 s of the journey. … … [1] [Total: 5]

9 0625/02/O/N/07 [Turn over For Examiner’s Use © UCLES 2007 7 A girl drops a small stone from a bridge into a pond. X Fig. 7.1 (a) The stone hits the water surface at point X. Fig. 7.2, which is drawn full-size, shows the wavefront a fraction of a second after the stone hits the water. (i) The wave travels at 5 cm / s. Calculate how far the wave travels in 0.3 s. distance travelled = … cm [1] (ii) On Fig. 7.2, draw the position of the wavefront 0.3 s after that already shown. [2] X Fig. 7.2 (b) A ringing bell also sends out waves in all directions. State two ways in which these waves are different from the waves in part (a), other than the fact that one is created in air and the other in water. 1. … 2. … [2] [Total: 5]

10 0625/02/O/N/07 For Examiner’s Use © UCLES 2007 8 An object OX is placed in front of a converging lens. The lens forms an image IY. Fig. 8.1 shows two rays from the object to the image. X O I Y Fig. 8.1 (a) On Fig. 8.1, (i) clearly mark and label the principal focus and the focal length of the lens, [3] (ii) draw a third ray from X to Y. [1]

11 0625/02/O/N/07 [Turn over For Examiner’s Use © UCLES 2007 (b) The following list contains descriptions that can be applied to images. Tick any which apply to the image shown in Fig. 8.1. real virtual enlarged diminished inverted upright image distance less than object distance image distance more than object distance [4] (c) State two things that happen to the image in Fig. 8.1 when the object is moved further away from the lens. 1. … 2. … [2] [Total: 10]

12 0625/02/O/N/07 For Examiner’s Use © UCLES 2007 9 A thermistor connected to a variable voltage supply is immersed in a beaker of water. The beaker of water is heated slowly, using a Bunsen burner, as shown in Fig. 9.1. variable voltage supply A V thermometer water Bunsen burner Fig. 9.1 At different temperatures, the voltage is adjusted until the current is 25 mA and the value of the voltage is noted. The results are shown below. temperature / °C 15 30 45 60 75 90 voltage / V 18.8 8.8 4.7 2.6 1.5 1.2 (a) On the axes of Fig. 9.2, shown on page 13, plot a graph of voltage against temperature. [4]

13 0625/02/O/N/07 [Turn over For Examiner’s Use © UCLES 2007 0 20 40 60 80 100 25 20 15 10 5 0 voltage / V temperature / oC Fig. 9.2 (b) From the graph, find the voltage needed to give a current of 25 mA (i) at 40 °C, voltage needed = … V [1] (ii) at 80 °C. voltage needed = … V [1] (c) Use your results in (b) to calculate the resistance of the thermistor (i) at 40 °C, resistance at 40 °C = … (ii) at 80 °C. resistance at 80 °C = … [5] (d) Use your results in (c) to complete the following sentence about thermistors of the sort used in this experiment. The thermistor in this experiment is a device whose resistance ………………………… as the temperature increases. [1] [Total: 12]

14 0625/02/O/N/07 For Examiner’s Use © UCLES 2007 10 A coil of insulated wire is connected in series with a battery, a resistor and a switch. Fig. 10.1 (a) The switch is closed and the current in the coil creates a magnetic field. (i) On Fig. 10.1, draw the shape of the magnetic field, both inside and outside the coil. [4] (ii) A glass bar, an iron bar and a perspex bar are placed in turn inside the coil. Which one makes the field stronger? … [1] (b) Two thin iron rods are placed inside the coil as shown in Fig. 10.2. The switch is then closed. Fig. 10.2 The iron rods move apart. Suggest why this happens. … … [3] [Total: 8]

15 0625/02/O/N/07 [Turn over For Examiner’s Use © UCLES 2007 11 The activity of a sample of radioactive material is determined every 10 minutes for an hour. The results are shown in the table. time / minutes 0 10 20 30 40 50 60 activity count / s 461 332 229 162 106 81 51 (a) From the figures in the table, estimate the half-life of the radioactive material. half-life = … minutes [1] (b) A second experiment is carried out with another sample of the same material. At the start of the experiment, this sample has twice the number of atoms as the first sample. Suggest what values might be obtained for (i) the activity at the start of the second experiment, … count / s [1] (ii) the half-life of the material in the second experiment. … minutes [1] (c) Name one type of particle that the material might be emitting in order to cause this activity. … [1] [Total: 4]

16 0625/02/O/N/07 For Examiner’s Use © UCLES 2007 12 A beam of cathode rays is travelling in a direction perpendicularly out of the page. The beam is surrounded by four metal plates P1, P2, P3 and P4 as shown in Fig. 12.1. On Fig. 12.1, the beam is shown as the dot at the centre. Q P1 P2 P4 P3 Fig. 12.1 (a) Cathode rays are produced by thermionic emission. What is the name of the particles which make up cathode rays? … [1] (b) A potential difference is applied between P1 and P3, with P1 positive with respect to P3. State what happens to the beam of cathode rays. … [2] (c) The potential difference in (b) is removed. Suggest how the beam of cathode rays can now be deflected down the page towards Q. … … [2] (d) Cathode rays are invisible. State one way to detect them. … [1] [Total: 6] Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity. University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education MARK SCHEME for the October/November 2007 question paper 0625 PHYSICS 0625/02 Paper 2 (Core Theory), maximum raw mark 80 This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. It shows the basis on which Examiners were instructed to award marks. It does not indicate the details of the discussions that took place at an Examiners’ meeting before marking began. All Examiners are instructed that alternative correct answers and unexpected approaches in candidates’ scripts must be given marks that fairly reflect the relevant knowledge and skills demonstrated. Mark schemes must be read in conjunction with the question papers and the report on the examination. • CIE will not enter into discussions or correspondence in connection with these mark schemes. CIE is publishing the mark schemes for the October/November 2007 question papers for most IGCSE, GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level syllabuses. www.XtremePapers.com

Page 2 Mark Scheme Syllabus Paper IGCSE – October/November 2007 0625 02 © UCLES 2007 NOTES ABOUT MARK SCHEME SYMBOLS B marks are independent marks, which do not depend on any other marks. For a B mark to be scored, the point to which it refers must actually be seen in the candidate's answer. M marks are method marks upon which accuracy marks (A marks) later depend. For an M mark to be scored, the point to which it refers must be seen in a candidate's answer. If a candidate fails to score a particular M mark, then none of the dependent A marks can be scored. C marks are compensatory method marks which can be scored even if the points to which they refer are not written down by the candidate, provided subsequent working gives evidence that they must have known it. e.g. if an equation carries a C mark and the candidate does not write down the actual equation but does correct working which shows he knew the equation, then the C mark is scored. A marks are accuracy or answer marks which either depend on an M mark, or which are one of the ways which allow a C mark to be scored. c.a.o. means "correct answer only". e.c.f. means "error carried forward". This indicates that if a candidate has made an earlier mistake and has carried his incorrect value forward to subsequent stages of working, he may be given marks indicated by e.c.f. provided his subsequent working is correct, bearing in mind his earlier mistake. This prevents a candidate being penalised more than once for a particular mistake, but only applies to marks annotated "e.c.f." e.e.o.o. means "each error or omission". brackets ( ) around words or units in the mark scheme are intended to indicate wording used to clarify the mark scheme, but the marks do not depend on seeing the words or units in brackets. e.g. 10 (J) means that the mark is scored for 10, regardless of the unit given. underlining indicates that this must be seen in the answer offered, or something very similar. un.pen. means "unit penalty". An otherwise correct answer will have one mark deducted if the unit is wrong or missing. This only applies where specifically stated in the mark scheme. Elsewhere, incorrect or missing units are condoned. OR/or indicates alternative answers, any one of which is satisfactory for scoring the marks.

Page 3 Mark Scheme Syllabus Paper IGCSE – October/November 2007 0625 02 © UCLES 2007 QU. SCHEME MARK 1 (a) 60 (cm3) B1 (b) liquid surface lower than in cylinder C1 liquid surface level with 15 cm3 (± 5 cm3) A1 (c) less B1 [Total: 4] 2 (a) 200,000 (m3) B1 (b) D = M/V in any form B1 his (a) x 1.3 C1 260,000 c.a.o. A1 kg B1 (c) decreases M1 air expands OR density decreases A1 (d) hot air rises B1 [Total: 8] 3 (a) 7.5 (cmHg) C1 75 (cmHg) A1 (give C1, A1 for 1.0006 x 105 Pa or 1 x 105 Pa (N/m2) if unit given) (b) nothing OR (Torricellian) vacuum OR Hg vapour B1 (c) tube level lower B1 reservoir level higher (any amount) B1 (d) pressures on 2 surfaces equal (always) ) Hg levels equal (always) OR no Hg column ) any two B1+B1 no change when pressure changes ) [Total: 7]

Page 4 Mark Scheme Syllabus Paper IGCSE – October/November 2007 0625 02 © UCLES 2007 QU. SCHEME MARK 4 (a) (i) arrow labelled W, vertically (by eye) down from somewhere on either boat B1 (ii) arrow labelled F, down slope, between either boat and slipway B1 (b) (i) multiply W by (vertical) height raised OR Wh B1 (ii) multiply F by distance along slope OR Fs B1 (iii) add (i) and (ii) B1 (c) time taken B1 [Total: 6] 5 (a) oC B1 (b) (i) ICE marked at 0 B1 (ii) STEAM marked at 100 B1 (c) expansion/volume/pressure OF a gas ) expansion/length OF a solid ) resistance OF a resistor/thermistor/wire ) bending OF a bimetal strip ) any 2 B1+B1 e.m.f/voltage OF a thermocouple ) colour OF a hot surface ) colour change OF certain chemicals ) [Total: 5] 6 (a) (i) uniform acceleration B1 (ii) 9 (m/s) B1 (iii) s = vt in any form C1 90 (m) OR 10 x his (ii), evaluated A1 (b) average speed is lower B1 [Total: 5]

Page 5 Mark Scheme Syllabus Paper IGCSE – October/November 2007 0625 02 © UCLES 2007 QU. SCHEME MARK 7 (a) (i) 1.5 (cm) B1 (ii) circle centred on X, outside printed circle (circle need not be drawn with a compass, but must be carefully drawn) M1 diameter 4.5 cm by eye A1 (b) sound longitudinal, water transverse ) sound wave faster (than water wave) ) any 2 B1,B1 different frequency/wavelength ) [Total: 5] 8 (a) (i) principal focus unambiguously marked B1 focal length approximately indicated C1 focal length precisely indicated, from pole to principal focus A1 (ii) any ray from X to Y, correctly refracted at lens B1 (b) [mark in pairs, using ✓ +  = 0] real B1 diminished B1 inverted B1 image distance less B1 (c) gets smaller B1 gets closer to lens B1 [Total: 10] 9 (a) points correctly plotted (±½ small square) –1 e.e.o.o. B2 smooth curve through his points B1 reasonable thickness B1 (b) (i) 5.3 – 6.1 B1 (ii) 0.9 – 1.7 B1 (c) R = V/I in any form C1 division by 25 or 25 x 10–3 somewhere C1 (i) answer between 220 and 240 B1 (ii) answer between 40 and 60 B1 Ω shown in either (i) or (ii) B1 (d) answer compatible with his (c) B1 [Total: 12]

Page 6 Mark Scheme Syllabus Paper IGCSE – October/November 2007 0625 02 © UCLES 2007 QU. SCHEME MARK 10 (a) (i) shape appropriate outside coil (condone incomplete loops) M1 lines mostly parallel within coil A1 pattern roughly symmetrical A1 no lines touching or crossing A1 (ii) iron bar B1 (b) rods become magnetised M1 same direction A1 repel B1 [Total: 8] 11 (a) within range 18–20 (mins) B1 (b) (i) 922 or thereabouts B1 (ii) his (a) B1 (c) alpha OR beta B1 [Total: 4] 12 (a) electrons B1 (b) move M1 towards P1 A1 (c) idea of making both P3 and/or P4 positive B1 equal potential B1 (earthing of P1 and P2 not required for answer) (d) fluorescent screen OR any other appropriate method B1 [Total: 6]