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1 PMT Cambridge International Examinations Cambridge International Advanced Subsidiary and Advanced Level PHYSICS 9702/53 Paper 5 Planning, Analysis and Evaluation May/June 207 MARK SCHEME Maximum Mark: 30 Published 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 befe marking began, which would have considered the acceptability of alternative answers. Mark schemes should be read in conjunction with the question paper and the Principal Examiner Rept f Teachers. Cambridge will not enter into discussions about these mark schemes. Cambridge is publishing the mark schemes f the May/June 207 series f most Cambridge IGCSE, Cambridge International A and AS Level and Cambridge Pre-U components, and some Cambridge O Level components. IGCSE is a registered trademark. This document consists of 6 printed pages. UCLES 207 [Turn over

2 PMT 9702/53 Cambridge International AS/A Level Mark Scheme May/June 207 Defining the problem (sin) θ is the independent variable and v is the dependent variable vary (sin) θ and measure v keep s (PQ) constant Methods of data collection labelled diagram showing inclined plane with labelled suppt and P and Q marked method to measure angle e.g. use a protract to measure θ use a ruler to measure marked distances from which sin θ θ may be determined method of timing f an appropriate distance to determine v (at Q) e.g. use a stopwatch/timer crectly positioned light gate(s) connected to a timer/data-logger crectly positioned motion sens connected to data-logger measurement of an appropriate distance to determine v (at Q) e.g. rule to measure an appropriate length length of a card to interrupt light beam distance from motion sens to Q Method of analysis plot a graph of v 2 against sin θ relationship valid if a straight line produced (not passing through the igin) B+ m g = gradient 2ms B+ m g = y-intercept 2Bs UCLES 207 Page 2 of 6

3 9702/53 Cambridge International AS/A Level Mark Scheme May/June 207 PMT Additional detail including safety considerations Max. 6 D use cushion/foam/sandbox f falling body (B) D2 (sin) θ determined using trigonometry relationship using marked lengths D3 appropriate equation to determine v (at Q) e.g. v = 2s t D4 repeat experiment f each θ and average v t D5 use of balance to measure mass of wooden block m and falling body B and rule to measure s 2Bsg D6 y-intercept =. B + m D7 clean surfaces of blocks/inclined plane/ensure surface of the plane is smooth D8 keep B and m constant keep mass of block and mass of falling body constant D9 method to ensure that wooden block starts at the same position P, e.g. put a mark on the block align front back of block D0 method to prevent plane slipping so that angle being measured remains the same, e.g. a mass as a stop UCLES 207 Page 3 of 6

4 9702/53 Cambridge International AS/A Level Mark Scheme May/June 207 PMT 2(a) gradient = 2 v y-intercept = 2L v 2(b) 0.80 ± ± ± ± ± First mark f all values of t crect. Second mark f uncertainties crect ± 0.0 2(c)(i) Six points plotted crectly. Must be accurate to less than half a small square. No blobs. Diameter of points must be less than half a small square. Err bars in t plotted crectly. All err bars to be plotted. Length of bar must be accurate to less than half a small square and symmetrical. UCLES 207 Page 4 of 6

5 9702/53 Cambridge International AS/A Level Mark Scheme May/June 207 PMT 2(c)(ii) 2(c)(iii) Line of best fit drawn. If points are plotted crectly then upper end of line should pass between (4.8, 0.76) and (5.6, 0.76) and lower end of line should pass between (7.6, 0.64) and (8.8, 0.64). Line should not be from first to last plot. Wst acceptable line drawn (steepest shallowest possible line). All err bars must be plotted. Gradient determined with a triangle that is at least half the length of the drawn line. Gradient must be negative. uncertainty = gradient of line of best fit gradient of wst acceptable line uncertainty = ½ (steepest wst line gradient shallowest wst line gradient) 2(c)(iv) y-intercept read-off y-axis to less than half small square determined by substitution into y = mx + c. 2(d)(i) uncertainty = y-intercept of line of best fit y-intercept of wst acceptable line uncertainty = ½ (steepest wst line y-intercept shallowest wst line y-intercept) v determined from gradient and units f v and L crect with crect power of ten. 2 2 v = = gradient 2(c)(iii) L determined from y-intercept and v and L given to 2 3 significant figures. Crect substitution of numbers must be seen. -intercept (c)(iv) L = v y -intercept = v (c)(iv) = y = 2 2 gradient (c)(iii) UCLES 207 Page 5 of 6

6 PMT 9702/53 Cambridge International AS/A Level Mark Scheme May/June 207 2(d)(ii) % uncertainty in v = % uncertainty in gradient % uncertainty in L = % uncertainty in y-intercept + % uncertainty in gradient % uncertainty in L = % uncertainty in y-intercept + % uncertainty in v Crect substitution of numbers must be seen. Maximum/minimum methods: max y-intercept Max L = max y-intercept max v mingradient min y-intercept Min L = min y-intercept min v max gradient UCLES 207 Page 6 of 6