Cambridge A Level Physics 9702 — 2010 Oct/Nov Paper 3 · Variant 4

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 fl uid. DO NOT WRITE IN ANY BARCODES. Answer both questions. You will be allowed to work with the apparatus for a maximum of one hour for each question. You are expected to record all your observations as soon as these observations are made, and to plan the presentation of the records so that it is not necessary to make a fair copy of them. You may lose marks if you do not show your working or if you do not use appropriate units. Additional answer paper and graph paper should be used only if it becomes necessary to do so. You are reminded of the need for good English and clear presentation in your answers. At the end of the examination, fasten all your work securely together. All questions in this paper carry equal marks. PHYSICS 9702/34 Advanced Practical Skills 2 October/November 2010 2 hours Candidates answer on the Question Paper. Additional Materials: As listed in the Confi dential Instructions. UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS General Certifi cate of Education Advanced Subsidiary Level and Advanced Level This document consists of 9 printed pages and 3 blank pages. [Turn over IB10 11_9702_34/3RP © UCLES 2010 *3072520809* For Examiner’s Use Total 1 2

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3 9702/34/O/N/10 © UCLES 2010 [Turn over For Examiner’s Use You may not need to use all of the materials provided. 1 In this experiment, you will investigate the equilibrium position of a metre rule that is balanced on a curved surface. (a) Mount the cylinder provided on its side on the board, wedging it with modelling clay, as shown in Fig. 1.1. If the cylinder has a lip, this should hang over the edge of the board, as shown. modelling clay lip sandpaper strip board Fig. 1.1 (side view) Note that the sandpaper strip is on the top of the cylinder. (b) One of the metre rules has a cotton loop, fi xed at the 65 cm mark. Balance this metre rule on the sandpaper strip so that it is parallel to the bench, as shown in Fig. 1.2. h1 h2 modelling clay board metre rule cotton loop Fig. 1.2 (end view) bench (c) Measure and record the heights h1 and h2 from the bench to the bottom of each end of the metre rule (see Fig. 1.2). h1 = ………………………… cm h2 = ………………………… cm

4 9702/34/O/N/10 © UCLES 2010 For Examiner’s Use (d) (i) Open out three paperclips as shown in Fig. 1.3. Fig. 1.3 (ii) Hang the three paperclips from the cotton loop and measure and record h1 and h2. h1 = … cm h2 = … cm (iii) In (ii), the number n of paperclips was 3. Now increase n and measure h1 and h2 again until you have six sets of values for n, h1 and h2. Include in your table of results values for and . (e) (i) Plot a graph of on the y-axis against on the x-axis. (ii) Draw the straight line of best fi t. (iii) Determine the gradient and y-intercept of this line. gradient = … y-intercept = … 1 (h1 – h2) 1 (h1 – h2) 1 n 1 n

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6 9702/34/O/N/10 © UCLES 2010 For Examiner’s Use (f) It is suggested that the relationship between h1, h2 and n is = + b where a and b are constants. Using your answers from (e)(iii), determine the values of a and b. Give appropriate units. a = … b = … 1 (h1 – h2) a n

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8 9702/34/O/N/10 © UCLES 2010 For Examiner’s Use You may not need to use all of the materials provided. 2 In this experiment, you will investigate water fl ow through a hole in a container. You are provided with a transparent plastic bottle with a small hole drilled in its base and with labels marking two positions P and Q. The apparatus has been set up for you as shown in Fig. 2.1. h Q P tray clamp beaker of water hole labels Fig. 2.1 (a) (i) Remove the bottle from the clamp and measure the diameter d of the bottle at position Q. d = … cm (ii) Calculate the cross-sectional area A of the bottle at position Q, using the relationship A = . A = … cm2 πd 2 4

9 9702/34/O/N/10 © UCLES 2010 [Turn over For Examiner’s Use (b) On the label at position Q, there are two horizontal lines, as shown in Fig. 2.2. h Q x Fig. 2.2 (i) Measure and record the distance x between the lines at position Q. x = … cm (ii) Estimate the percentage uncertainty in x. percentage uncertainty = … (c) (i) Calculate the volume V of the bottle between the lines at position Q using the relationship V = Ax. V = … cm3 (ii) Measure and record the distance h between the base of the bottle and the lower line at position Q. h = … cm (d) (i) Locate the small hole in the base of the bottle. (ii) Replace the bottle in the clamp as in Fig. 2.1. Cover the hole in the base of the bottle with your fi nger and then add water to the bottle so that the water level is just above the lines at position Q. Replace the beaker under the bottle. (iii) Remove your fi nger so that water fl ows into the beaker and measure the time it takes for the water level to drop between the two lines at position Q. Record this time t. t = … s (iv) Calculate the fl ow rate R, using the relationship R = . Give an appropriate unit. R = … V t

10 9702/34/O/N/10 © UCLES 2010 For Examiner’s Use (e) (i) Remove the bottle from the clamp and repeat (b)(i) and (c) for the lines at position P, using your value of cross-sectional area from (a)(ii). x = … cm V = … cm3 h = … cm (ii) Repeat (d) for the lines at position P. t = … s R = … (f) (i) It is suggested that the relationship between R and h is R = kh where k is a constant. Using your data, calculate two values of k. k for position Q = … k for position P = … (ii) Explain whether your results support the suggested relationship. … … … … …

11 9702/34/O/N/10 © UCLES 2010 For Examiner’s Use (g) (i) Describe four sources of uncertainty or limitations of the procedure in this experiment. 1. . … … 2. . … … 3. . … … 4. . … … (ii) Describe four improvements that could be made to this experiment. You may suggest the use of other apparatus or different procedures. 1. . … … 2. . … … 3. . … … 4. . … …

12 9702/34/O/N/10 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. BLANK PAGE © UCLES 2010

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS GCE Advanced Subsidiary Level and GCE Advanced Level MARK SCHEME for the October/November 2010 question paper for the guidance of teachers 9702 PHYSICS 9702/34 Paper 32 (Advanced Practical Skills 2), maximum raw mark 40 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, which would have considered the acceptability of alternative answers. 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 2010 question papers for most IGCSE, GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level syllabuses.

Page 2 Mark Scheme: Teachers’ version Syllabus Paper GCE AS/A LEVEL – October/November 2010 9702 34 © UCLES 2010 1 (c) Measurements for h1 and h2 to nearest mm [1] Check raw values if readings are repeated. The difference between h1 and h2 is < 2 mm. [1] (d) (iii) Six sets of readings of n, h1 and h2 scores 5 marks, five sets scores [5] 4 marks etc. Incorrect trend then –1. Help from supervisor then –1. Range – [1] n values must include 10 or greater. Column headings – [1] Each column heading must contain a quantity and a unit where appropriate. There must be some distinguishing mark between the quantity and the unit. E.g. h1/cm or h1(cm) but not 1/((h1 – h1)/cm). Consistency of presentation of raw readings – [1] All values of h1 and h2 must be given to the same precision. Significant figures – [1] S.f. for 1/(h1 – h2) must be the same as, or one more than, the s.f. in the difference (h1 – h2). Calculation – [1] 1/(h1 – h2) calculated correctly. (Graph) Axes – [1] Sensible scales must be used, no awkward scales (e.g. 3:10). Scales must be chosen so that the plotted points must occupy at least half the graph grid in both x and y directions. Scales must be labelled with the quantity which is being plotted. Ignore units. Scale markings must be no more than 3 large squares apart. Plotting of points – [1] All observations must be plotted. Do not accept blobs (points with diameter > half a small square). Ring and check a suspect plot. Tick if correct. Re-plot if incorrect. Work to an accuracy of half a small square. Line of best fit – [1] Judge by balance of at least 5 trend points about the candidate's line. There must be an even distribution of points either side of the line along the full length. Line must not be kinked. Quality – [1] Scatter of points must be less than ±0.02 on the 1/n axis about the examiner’s line. All points must be plotted (at least 5) for this mark to be scored.

Page 3 Mark Scheme: Teachers’ version Syllabus Paper GCE AS/A LEVEL – October/November 2010 9702 34 © UCLES 2010 (e) (iii) Gradient The hypotenuse must be at least half the length of the drawn line. [1] Both read-offs must be accurate to half a small square. Intercept [1] Check that the read-off or the method of calculation is correct. (f) Value of a = value of gradient and value of b = value of intercept. [1] Do not allow a value presented as a fraction. Units for a and b are correct. [1] E.g. cm–1 or m–1 but must be consistent with the values. Allow no unit for b if b = 0. [Total: 20] 2 (a) (i) Value of d in range 5 cm to 15 cm. [1] Help from supervisor then –1. Evidence of repeated measurements of d. [1] (ii) Correct calculation of A. [1] Do not allow a value in terms of π. (b) (i) Measurement for x in range 0.8 cm < x < 1.0 cm to nearest mm. [1] (ii) Absolute uncertainty 1 or 2 mm (or half the range of repeats), and correct method of calculation. [1] (c) (ii) Measurement for h to nearest mm. [1] (d) (iii) Value for t > 1 s and given to 0.1 s or 0.01 s. [1] Check raw data if there are repeats. (iv) Correct calculation of R, with consistent unit (e.g. cm3 s–1). [1] (e) (i) Values for x, V and h. [1] (ii) Correct trend (R increases with h). [1] (f) (i) Values of k calculated correctly. [1] (ii) Valid conclusion based on the calculated values of k. Candidate must test against a stated criterion. [1]

Page 4 Mark Scheme: Teachers’ version Syllabus Paper GCE AS/A LEVEL – October/November 2010 9702 34 © UCLES 2010 (g) (i) Problems 4 max (ii) Improvements 4 max No credit/not enough A Two readings are not enough (to draw a conclusion). Take more readings, and plot a graph/calculate more k values. More readings and calculate the average/ only one reading. B Bottle not circular/ diameter at P different to that at Q. Collect water and measure volume/remeasure diameter at P. C Bottle deforms when measuring d. Use vernier callipers to measure d. Use string to measure d. D Difficult to see water level/meniscus problems/refraction problems. Use coloured water/liquid. Use oil. E Labels get wet/ink runs Use waterproof labels/ink F Difficult to judge when to start/stop timing. Use video, with timing method. Human reaction time error. G Large uncertainty in x. Use travelling microscope to measure x. X Another valid point E.g. Flowrate calculated is not the flowrate at h. E.g. Measure h to point midway between marks. Move marks closer together. Ignore ‘parallax problems’ unless there is a convincing diagram. Ignore ‘use assistant’. Ignore ‘use distance sensor’ unless there is a convincing diagram. Ignore ‘use a computer/datalogger/light gates’. Ignore ‘bottle not vertical’. [Total: 20]