Cambridge IGCSE Physics 0625 — 2005 Oct/Nov Paper 3 · Variant 1

This document consists of 14 printed pages and 2 blank pages. SP (SJF3441/CG) T03202/4 © UCLES 2005 [Turn over UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education PHYSICS Paper 3 Extended 0625/03 October/November 2005 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 in the spaces provided on the Question Paper. You may use a soft pencil for any diagrams, graphs, music or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. Answer all questions. At the end of the examination, fasten all your work securely together. Take the weight of 1 kg to be 10 N (i.e. acceleration of free fall = 10 m/s2). The number of marks is given in brackets [ ] at the end of each question or part question. You may lose marks if you do not show your working or if you do not use appropriate units. DO NOT WRITE IN THE BARCODE. DO NOT WRITE IN THE GREY AREAS BETWEEN THE PAGES. For Examiner’s Use 1 2 3 4 5 6 7 8 9 10 11 Total www.XtremePapers.com

2 0625/03/O/N/05 © UCLES 2005 1 (a) State what is meant by the terms (i) weight, … … [1] (ii) density. … … [1] (b) A student is given a spring balance that has a scale in newtons. The student is told that the acceleration of free-fall is 10 m/s2. (i) Describe how the student could find the mass of an irregular solid object. … … … [2] (ii) Describe how the student could go on to find the density of the object. … … … … [2] (c) Fig. 1.1 shows three forces acting on an object of mass 0.5 kg. All three forces act through the centre of mass of the object. Fig. 1.1 Calculate (i) the magnitude and direction of the resultant force on the object, magnitude = ……………… direction … [2] (ii) the magnitude of the acceleration of the object. acceleration =…………………… [2] For Examiner’s Use 4.0 N 9.0 N 3.0 N centre of mass

3 0625/03/O/N/05 © UCLES 2005 [Turn over 2 Fig. 2.1 shows apparatus for investigating moments of forces. Fig. 2.1 The uniform metre rule shown in Fig. 2.1 is in equilibrium. (a) Write down two conditions for the metre rule to be in equilibrium. condition 1 … … … condition 2 … … … [2] (b) Show that the value of the reading on the spring balance is 8.0 N. [2] (c) The weight of the uniform metre rule is 1.5 N. Calculate the force exerted by the pivot on the metre rule. magnitude of force = ………………………………… direction of force ………………………………… [2] For Examiner’s Use 0 10 20 30 40 50 horizontal pivot 6.0 N weight horizontally balanced metre rule spring balance 60 70 80 90 100

4 0625/03/O/N/05 © UCLES 2005 For Examiner’s Use 3 Fig. 3.1 shows a pond that is kept at a constant depth by a pressure-operated valve in the base. Fig. 3.1 (a) The pond is kept at a depth of 2.0 m. The density of water is 1000 kg/m3. Calculate the water pressure on the valve. pressure =…………………….. [2] (b) The force required to open the valve is 50 N. The valve will open when the water depth reaches 2.0 m. Calculate the area of the valve. area = ……………………….. [2] (c) The water supply is turned off and the valve is held open so that water drains out through the valve. State the energy changes of the water that occur as the depth of the water drops from 2.0 m to zero. … … [2] spring outlet pressure-operated valve water

5 0625/03/O/N/05 © UCLES 2005 [Turn over For Examiner’s Use 4 Fig. 4.1 shows apparatus that could be used to measure the specific latent heat of ice. Fig. 4.1 (a) Describe how you would use the apparatus. You may assume that ice at 0 °C and a stopwatch are available. State all the readings that would be needed at each stage. … … … … … [4] (b) In an experiment, 120 g of ice at 0 °C is to be melted. The specific latent heat of ice is 340 J/g. Assume that all the energy from the heater will be used to melt the ice. Calculate the expected time for which the 60 W heater is switched on. expected time = …………………… [2] (c) When the experiment is carried out, the ice melts in slightly less time than the expected time. (i) State one reason why this happens. … … [1] (ii) Suggest one modification to the experiment that would reduce the difference between the experimental time and the expected time. … … [1] power supply melting ice at 0 °C beaker 60 W heater

6 0625/03/O/N/05 © UCLES 2005 5 Fig. 5.1 shows a way of indicating the positions and direction of movement of some molecules in a gas at one instant. Fig. 5.1 (a) (i) Describe the movement of the molecules. … [1] (ii) Explain how the molecules exert a pressure on the container walls. … … [1] (b) When the gas in the cylinder is heated, it pushes the piston further out of the cylinder. State what happens to (i) the average spacing of the molecules, … [1] (ii) the average speed of the molecules. … [1] (c) The gas shown in Fig. 5.1 is changed into a liquid and then into a solid by cooling. Compare the gaseous and solid states in terms of (i) the movement of the molecules, … … [1] (ii) the average separation of the molecules. … … [1] For Examiner’s Use cylinder piston

7 0625/03/O/N/05 © UCLES 2005 [Turn over 6 Fig. 6.1 shows the path of a sound wave from a source X. Fig. 6.1 (a) State why a person standing at point Y hears an echo. … [1] (b) The frequency of the sound wave leaving X is 400 Hz. State the frequency of the sound wave reaching Y. frequency = ……………….. [1] (c) The speed of the sound wave leaving X is 330 m/s. Calculate the wavelength of these sound waves. wavelength = ………………………. [2] (d) Sound waves are longitudinal waves. State what is meant by the term longitudinal. … … [1] For Examiner’s Use Y X path of sound wave wall

8 0625/03/O/N/05 © UCLES 2005 7 (a) Fig. 7.1 shows two rays of light from a point O on an object. These rays are incident on a plane mirror. Fig. 7.1 (i) On Fig. 7.1, continue the paths of the two rays after they reach the mirror. Hence locate the image of the object O. Label the image I. [2] (ii) Describe the nature of the image I. … … [2] (b) Fig. 7.2 is drawn to scale. It shows an object PQ and a convex lens. Fig. 7.2 For Examiner’s Use O F F principal focus principal focus principal position of convex lens axis Q P

9 0625/03/O/N/05 © UCLES 2005 [Turn over (i) On Fig. 7.2, draw two rays from the top of the object P that pass through the lens. Use these rays to locate the top of the image. Label this point T. [3] (ii) On Fig. 7.2, draw an eye symbol to show the position from which the image T should be viewed. [1] For Examiner’s Use

10 0625/03/O/N/05 © UCLES 2005 8 Fig. 8.1 shows a high-voltage supply connected across two metal plates. Fig. 8.1 When the supply is switched on, an electric field is present between the plates. (a) Explain what is meant by an electric field . … [2] (b) On Fig. 8.1, draw the electric field lines between the plates and indicate their direction by arrows. [2] (c) The metal plates are now joined by a high-resistance wire. A charge of 0.060 C passes along the wire in 30 s. Calculate the reading on the ammeter. ammeter reading = ……………………… [2] (d) The potential difference of the supply is re-set to 1500 V and the ammeter reading changes to 0.0080 A. Calculate the energy supplied in 10 s. Show your working. energy = ………………. [3] A high-voltage supply metal plates + – For Examiner’s Use

11 0625/03/O/N/05 © UCLES 2005 [Turn over 9 (a) In the space provided, draw the symbol for a NOR gate. Label the inputs and the output. [2] (b) State whether the output of a NOR gate will be high (ON) or low (OFF) when (i) one input is high and one input is low, … (ii) both inputs are high. … [1] (c) Fig. 9.1 shows a digital circuit made from three NOT gates and one NAND gate. Fig. 9.1 (i) Write HIGH or LOW in each of the boxes on Fig. 9.1. [2] (ii) State the effect on the output of changing both of the inputs. … … [1] For Examiner’s Use HIGH LOW

12 0625/03/O/N/05 © UCLES 2005 10 Fig. 10.1 shows the basic parts of a transformer. Fig. 10.1 (a) Use ideas of electromagnetic induction to explain how the input voltage is transformed into an output voltage. Use the three questions below to help you with your answer. What happens in the primary coil? … … … … What happens in the core? … … What happens in the secondary coil? … … … [5] (b) State what is needed to make the output voltage higher than the input voltage. … [1] For Examiner’s Use primary coil input secondary coil X X Y Y output

13 0625/03/O/N/05 © UCLES 2005 [Turn over (c) The core of this transformer splits along XX and YY. Explain why the transformer would not work if the two halves of the core were separated by about 30 cm. … … [1] (d) A 100% efficient transformer is used to step up the voltage of a supply from 100 V to 200 V. A resistor is connected to the output. The current in the primary coil is 0.4 A. Calculate the current in the secondary coil. current = …………………… [2] For Examiner’s Use

14 0625/03/O/N/05 © UCLES 2005 11 A radioactive source emits only β-particles. (a) A scientist wishes to investigate the deflection of β-particles by an electric field. Draw a labelled diagram to suggest a suitable experimental arrangement. [3] (b) State how the apparatus would be used to show the deflection of the β-particles by the electric field. … … … [2] (c) State how the results would show the deflection of the β-particles. … … [1] (d) Explain the direction of the deflection obtained. … … [1] For Examiner’s Use

16 0625/03/O/N/05 BLANK PAGE 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 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 November 2005 question paper 0625 PHYSICS 0625/03 Paper 3 (Extended) maximum raw mark 80 This mark scheme is published as an aid to teachers and students, to indicate the requirements of the examination. It shows the basis on which Examiners were initially instructed to award marks. It does not indicate the details of the discussions that took place at an Examiners’ meeting before marking began. Any substantial changes to the mark scheme that arose from these discussions will be recorded in the published Report on the Examination. 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. The minimum marks in these components needed for various grades were previously published with these mark schemes, but are now instead included in the Report on the Examination for this session. • CIE will not enter into discussion or correspondence in connection with these mark schemes. CIE is publishing the mark schemes for the November 2005 question papers for most IGCSE and GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level syllabuses. www.XtremePapers.com

Page 1 Mark Scheme Syllabus Paper IGCSE – November 2005 0625 3 © University of Cambridge International Examinations 2005 1 (a) (b) (i) (iii) (c) (i) (ii) force of gravity on a mass or mg mass/volume hang object from spring balance, reading in N taken divide reading in N by 10 or g volume of water in cylinder or fill overflow can to top add object find increase in volume or measure overflow volume {no credit for mass unless not scored in (i) and no credit for density = mass/ volume unless not scored in a) } 2N left F = ma or 2 = 0.5 a a = 4.0 m/s2 B1 B1 B1 B1 B1 B1 B1 B1 C1 A1 [2] [4] [4] Total [10] 2 (a) (b) (c) upwards force = downwards force or no resultant force opposing moments equal or A.C.M. = C. M. 30 x spring balance reading = 40 x 6.0 or equivalent spring balance reading = 8.0 N 0.5 N downwards B1 B1 C1 A1 B1 B1 [2] [2] [2] Total [6] 3 (a) (b) (c) P = hdg or 2 x 1000 x 10 = 20 000 N/m2 or Pa p = f/a or 20 000 = 50/a a = 0.0025 m2 potential energy of the water converted to kinetic energy of water through outlet (and heat) C1 A1 C1 A1 B1 B1 [2] [2] [2] Total[6] 4 (a) (b) (c) (i) (ii) turn on heater and wait until water starts dripping in beaker empty beaker & replace, start watch stop watch & remove beaker at same time record time find and record mass of water in beaker 60 x t = 120 x 340 t = 680 s ice gains heat from surroundings/ice falls through funnel lag or fit lid to funnel/place gauze in funnel bottom B1 B1 B1 B1 B1 C1 A1 B1 B1 [M4] [2] [2] Total [8]

Page 2 Mark Scheme Syllabus Paper IGCSE – November 2005 0625 3 © University of Cambridge International Examinations 2005 5 (a) (i) (ii) (b) (i) (ii) (c) (i) (ii) random hit and rebound increase or further apart increase or move faster random, fast in gas to vibration in solid long way apart in gas to very close or touching B1 B1 B1 B1 B1 B1 [2] [2] [2] Total [6] 6 (a) (b) (c) (d) Sound reflects off wall 400 Hz λ = v/f or = 330/400 = 0.83 m vibration/oscillation along line of/direction of wave B1 B1 C1 A1 B1 [1] [1] [2] [1] Total [5] 7 (a) (i) (ii) (b) (i) (ii) two approximately correct reflections evidence of projecting back to image or use of equal distance from the mirror, object and image virtual any one of upright, same size, same distance from mirror ray 1 correct ray 2 correct image correctly located eye symbol to right of lens B1 B1 B1 B1 B1 B1 B1 B1 [4] [4] Total [8] 8 (a) (b) (c) (d) force is produced on any charge placed in the field at least 3 parallel, straight lines plate to plate, ignore end effect at least one correct arrow, none wrong q = It or 0.06 = I x 30 I = 0.002 A or 2 mA E = Vit = 1500 x 0.008 x 10 = 120 J B1 B1 B1 B1 C1 A1 C1 C1 A1 [2] [2] [2] [3] Total [9]

Page 3 Mark Scheme Syllabus Paper IGCSE – November 2005 0625 3 © University of Cambridge International Examinations 2005 9 (a) (b) (i) (ii) (c) (i) (ii) correct symbol correct labels low, OFF or 0 low, OFF or 0 need both correct need 4 boxes correct for 2 marks, -1 for e.e.o.e. no change B1 B1 B1 B2 B1 [2] [1] [3] Total [6] 10 (a) (i) (ii) (iii) (b) (c) (d) a.c. input causes constantly changing current through coil magnetic field formed in or around coil constantly changing magnetic field (changing) magnetic field transferred to secondary coil (changing) magnetic field cuts secondary coil induces e.m.f. more turns on secondary (than on primary) no transfer of magnetic field from primary to secondary Vp.Ip = Vs. Is or 100 x 0.4 = 200 x Is Is = 0.2 A B1 B1 B1 B1 B1 B1 B1 B1 C1 A1 [M2] [3] [1] [1] [2] Total [9] 11 (a) (b) (c) (d)
β -source and detector suitably arranged deflecting plates suitably arranged additional detail e.g. slit or collimator, vacuum chamber, circuit connected to deflecting plates at least 3 readings at right angles beyond & perp. to the plates one near +ve, one near –ve and one in centre highest reading near +ve plate electrons negatively charged, attracted to +ve B1 B1 B1 M1 A1 B1 B1 [3] [2] [1] [1] Total [7]