2006 Physics. Advanced Higher. Finalised Marking Instructions

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1 006 Physics Advanced Higher Finalised Marking Instructions The Scottish Qualifications Authority 006 The information in this publication may be reproduced to support SQA qualifications only on a non-commercial basis. If it is to be used for any other purposes written permission must be obtained from the Assessment Materials Team, Dalkeith. Where the publication includes materials from sources other than SQA (secondary copyright), this material should only be reproduced for the purposes of examination or assessment. If it needs to be reproduced for any other purpose it is the centre's responsibility to obtain the necessary copyright clearance. SQA's Assessment Materials Team at Dalkeith may be able to direct you to the secondary sources. These Marking Instructions have been prepared by Examination Teams for use by SQA Appointed Markers when marking External Course Assessments. This publication must not be reproduced for commercial or trade purposes.

2 Detailed Marking Instructions AH Physics Numerical Marking (a) (b) (c) (d) (e) The fine divisions of marks shown in the marking scheme may be recorded within the body of the script beside the candidate s answer. If such marks are shown they must total to the mark in the inner margin. Negative marks or marks to be subtracted should not be shown. An inverted vee may be used instead. The number recorded should always be the marks being awarded. The number out of which a mark is scored SHOULD NEVER BE SHOWN AS A DENOMINATOR. (½ mark will always mean one half mark and never 1 out of.) Where square ruled paper is enclosed inside answer books it should be clearly indicated that this item has been considered. Marks awarded should be transferred to the script booklet inner margin and marked G. Fractional marks, if awarded to individual questions, should be recorded in the grid, but the total script mark must be rounded up to the next whole number when transferred to the box at the top of the script.. Other Marking Symbols which may be used TICK Correct point as detailed in scheme, includes data entry SCORE THROUGH Any part of answer which is wrong. (For a block of wrong answer indicate zero marks.) INVERTED VEE A point omitted which has led to a loss of marks. WAVY LINE Under an answer worth marks which is wrong only because a wrong answer has been carried forward from a previous part. G Reference to a graph on separate paper. You MUST show a mark on the graph paper and the SAME mark on the script. X Wrong Physics Wrong order of marks 3. Marking Symbols which may not be used. WP Marks not awarded because an apparently correct answer was due to the use of wrong physics. ARITH Candidate has made an arithmetic mistake. SIG FIGS or SF Candidate has made a mistake in the number of significant figures for a final answer. Page

3 4. General Instructions (Refer to National Qualifications Booklet) (a) (b) (c) (d) (e) (f) (g) (h) No marks are allowed for a description of the wrong experiment or one which would not work. Full marks should be given for information conveyed correctly by a sketch. Surplus answers: where a number of reasons, examples etc are asked for and a candidate gives more than the required number then wrong answers may be treated as negative and cancel out part of the previous answer. Full marks should be given for a correct answer to a numerical problem even if the steps are not shown explicitly. The part marks shown in the scheme are for use in marking partially correct answers. Where 1 mark is shown for the final answer to a numerical problem ½ mark may be deducted for an incorrect unit. Where a final answer to a numerical problem is given in the form 3-6 instead of then deduct ½ mark. Deduct ½ mark if an answer is wrong because of an arithmetic slip. No marks should be awarded in a part question after the application of a wrong physics principle (wrong formula, wrong substitution) unless specifically allowed for in the marking scheme. In certain situations, a wrong answer to a part of a question can be carried forward within that part of the question. This would incur no further penalty provided that it is used correctly. Such situations are indicated by a horizontal dotted line in the marking instructions. Wrong answers can always be carried forward to the next part of a question, over a solid line without penalty. (i) (j) (k) (l) ½ mark should be awarded for selecting a formula. Where a triangle type relationship is written down and then not used or used incorrectly then any partial ½ mark for a formula should not be awarded. In numerical calculations, if the correct answer is given then converted wrongly in the last line to another multiple/submultiple of the correct unit then deduct ½ mark. Significant figures. Data in question is given to 3 significant figures. Correct final answer is 8 16J. Final answer 8 J or 8 18J or 8 176J No penalty. Final answer 8J or J Deduct ½ mark. Candidates should be penalised for a final answer that includes three or more figures too many or two or more figures too few. ie accept two higher and one lower Max ½ mark deduction per question Max ½ deduction from question paper Page 3

4 (m) Squaring Error E K = ½ mv = ½ 4 = 4J (-½, ARITH) E K = ½ mv = ½ 4 = 4J (½, formula) Incorrect substitution. The General Marking Instructions booklet should be brought to the markers' meeting. Page 4

5 Physics Marking Issues The current in a resistor is 1 amperes when the potential difference across it is 7 volts. Calculate the resistance of the resistor. 1. V=IR 7 =1 R R= 0Ω Answers Mark +comment Issue (1) Ideal Answer. 0Ω () Correct Answer GMI (1½) Unit missing GMI (a) Ω (0) No evidence/wrong Answer GMI 1. Ω (0) No final answer GMI V 7 (1½) Arithmetic error GMI 7 R= = =4 0Ω I 1 R= I V =4 0Ω Formula only GMI 4 and 1 R= I V = Ω Formula only GMI 4 and 1 V 7 (1) Formula + subs/no final answer GMI 4 and 1 R= = = Ω I 1 V 7 (1) Formula + substitution GMI (a) and 7 R= = =4 0 I 1 V 1 Formula but wrong substitution GMI R= = = 0Ω I 7 V 7 Formula but wrong substitution GMI R= = = 0Ω I 1 I 7 (0) Wrong formula GMI R= = = 0Ω V V=IR 7 =1 x R R=0 Ω (1½) Arithmetic error GMI 7 1. V=IR I 1 Formula only GMI 0 R= = =0 Ω V 7 Page

6 Data Sheet Common physical Quantities Quantity Symbol Value Quantity Symbol Value Gravitational acceleration on Earth Radius of Earth Mass of Earth Mass of Moon Mean of Radius of Moon Orbit Universal constant of gravitation Speed of light in vacuum Speed of sound in air g R E M E M M G c v 9 8 ms x 10 6 m 6 0 x 10 4 kg 7 3 x 10 kg 3 84 x 10 8 m 6 67 x m 3 kg -1 s x 10 8 ms x 10 ms -1 Mass of electron Charge on electron Mass of neutron Mass of proton Mass of alpha particle Charge on alpha particles Planck s constant Permittivity of free space Permeability of free space M e e m n m p m a h ε 0 µ x kg x C 1 67 x 10-7 kg x 10-7 kg 1 64 x 10-7 kg 3 0 x C 6 63 x Js 8 8 x 10-1 Hm -1 4π x 10-7 Hm -1 Refractive Indices The refractive indices refer to sodium light of wavelength 89 nm and to substances at a temperature of 173 K. Substance Refractive index Substance Refractive index Diamond Glass Ice Perspex Glycerol Water Air Magnesium Fluoride Spectral Lines Element Wavelength/nm Colour Element Wavelength/nm Colour Hydrogen Red Blue-green Blue-violet Violet Ultraviolet Ultraviolet Cadmium Red Green Blue Lasers Element Wavelength/nm Colour Sodium 89 Yellow Carbon-dioxide Helium-neon Infrared Red Page 6

7 Properties of selected Materials Substance Aluminium Copper Glass Ice Gylcerol Methanol Sea Water Water Air Hydrogen Nitrogen Oxygen Density/ Kg m x x x x x x x x x Melting Point/K Boiling Point/K Specific Heat Capacity/ Jkg -1 K x x x x x 10 3 x x x x x x 10 Specific Latent Heat of Fusion/ Jkg x 10 0 x x x x x Specific latent Heat of Vaporisation/ Jkg x x x x x x 10 The gas densities refer to a temperature of 73 K and pressure of 1 01 x 10 Pa. Page 7

8 006 AH Physics 1(a)(i)(A) t = sum number -OR - t = t = 0 00 = T = = 0 00s 0 (B) uncertainty = max min N uncertainty = uncertainty = 0 00 = uncertainty in T = = s 0 T= (1) T= 00 = 0 00s OR %age uncertainty in T = 1% (1) = s OR uncertainty = (1) uncertainty in T = 0 0 uncertainty in T = s 3 14 (a)(ii) F = mrω ω = π = π = 4π = 1 6 T 0 00 F = (4π) F = 1 8 N EITHER FORMULA MISSING MAX (1) F = mv r v = πr = π 0 00 = 6 8 T 0 00 F = 0 00 (π) 0 00 F = 1 8 N (a) (iii) % uncertainty in r = = 0 4% 0 00 % uncertainty in m = = 4% 0 00 % uncertainty in T = = 1% 0 00 % uncertainty in T = 1 = % % uncertainty in F = (4 + ) = 4 47% F = ( ) N (1) ALLOW CARRY THROUGH WRONG ANSWER FROM 1(a)(i)(B) Allow ( = 4 49% OR 4 % 4 Page 8

9 006 AH Physics (a) (iv) (A) (B) Tension Weight Tension Both label and direction necessary for each Accept W, mg and T Any mention of centripetal force or tangential force or centrifugal force Zero marks. Weight (a) (v) weight = mg = = 1 96 (N) T min = F c - W = = 13 8 N (1) 1 (b) Pitch decreases -OR- Sound is lower (1) 1 Page 9

10 006 AH Physics (a) (i) τ = F r 1 τ = τ = 0 0 N m (1) (a) (ii) α = ω - ω 0 t α = α = rad s - (1) (a) (iii) τ = I α 0 0 = I I = 0 0 = kg m (1) (b) (i) I = ½mr I = 0 3 (0 1) I = 0 03 kg m (1) (b) (ii) I 1 ω 1 = (I 1 + I )ω Accept I 1 ω 1 = I ω = ( )ω ω = 8 rad s -1 (1) (c) Resulting angular velocity LESS (1) I of the ring GREATER Correct statement with no justification or with justification involving WP Zero marks. Angular momentum CONSERVED ( so ω less ) I ω = 1½ Page 10

11 006 AH Physics 3 (a) (i) W Force exerted on 1 kg (of mass) M placed in the field (1) = 0 Must be in words 1 9 (a) (ii) (A) F = GmM r 3 F = mg mg = GmM M = gr G r START HERE = 1½ (B) M = 3 7 ( ) M = kg (1) (b) (i) F = GmM r r = ( ) = (m) data F = ( ) F = N (b) (ii) F = mrω ω = ω = (rad s -1 ) T = π = ω π T = s (1) If value of r incorrect, then maximum mark possible is 1. (½ for equation and ½ for data) for No formula = Max 1 v = ( GM / r) v = v = (m s -1 ) _ T = πr = π v T = s (1) 3 OR T = π R 3 = (1½) GM Page 11

12 006 AH Physics 4 (a) E k = ½mω (A - y ) No Equation = 0 marks E k = ½ 0 36 (( 10 - ) y ) E k = ½ 0 36( 10-3 y ) E k = 4 ( y ) (b) E k MAX = E k MAX = J (1) (c) E p = ½mω y E k = 4 ( 10-3 (0 04) ) = (J) E p = ½ 0 36 (0 04) E p = J (1) E p = E k MAX - E k = = J (1) Accept J Accept J Page 1

13 006 AH Physics No formula max 1 (½ + ½).(a)(i) V = 1. Q r = πε o r ε o = r = 0 36 max 1 (½ + ½) 8 10 = Q 1 4π no value shown for ε 0 = max 1 (½ + ½) 9 x 10 9 = data in place of ε 0 Q = C (a)(ii) 8 10 V (1) Missing V 1 (a)(iii)a E = 1. Q 4πε o r = π = N C -1 (1) Use r = 0 36 Wrong Q V E = W.P. r max max (a)(iii)b E curve. Curve must not touch r axis 1 r for zero inside sphere No labels/wrong labels deduct (b) r = 0 7 r = E = 1 Q 4πε o r = π = Vertical components sum to cos 4 = N C -1 (1) upwards or vertically up or straight up (1) vertically 6 99 upwards 10 4 r arrows for shape of diag Page 13

14 006 AH Physics 6.(a) F = E Q = = N (1) Allow ve sign for charge 10 (b) W = mg = = << Fe GMm If F = then r (c) a = F m = = ( m s - ) t = l = v 0 = ( s) 4 s = (ut) + 1 at = ( ) = m (1) (d) n = Q e = data = Page 14

15 006 AH Physics 7.(a) (i) 1 qv = mv q = data m = data = v (v = m s -1 ) If no equation then max (1) 1 (a) (ii) Bqv = mv => r r = mv Bq r = = m (1) mv r = (1½) Bq Accept 0 00 m 3 (a) (iii) E k doubled so v increased by (1) v = E k FINAL = E k INITIAL + qv = (or qv) OR 1 mv = 1 mu + qv = m s -1 (1) Substitution v = m s -1 (1) (b) E k = 1 Q 1 Q (1) 4πε o r 3 subs = 1 4π r 19 q of gold = data r = m (1) Accept 1 1 x m (value of constant) (c) m = m 0 v 1 c = v 8 (3 10 ) v = m s -1 (1) Page 1

16 006 AH Physics 8(a) Value of resistor R (1) Accept resistance 1 6 (b) E = - L di dt - 9 = - L 1 L = 0 7 H (1) If only one ve sign in second line then only mark for equation. (c) E = 1 LI = (0 1) = J (1) (d) di dt very high or 1 rapid decay (or collapse) of magnetic field (1) Page 16

17 006 AH Physics 9.(a)(i) Strong (force) (1) 1 6 (a)(ii) A u + 1d (1) Accept arrow notation. B 1u + d (1) (b) weak (force) (1) 1 (c) λ = h mv = = m (1) Page 17

18 006 AH Physics 10 (a) Nodes (1) 1 8 (b) (i) v = fλ λ = λ = (m) v = v = 30 m s -1 (1) Accept 360 m s -1 (early rounding) 3 (b) (ii) Measure distance between > nodes or Decrease frequency to increase λ or Decrease frequency to increase node separation (1) This will decrease uncertainty in measurement of λ (1) (c) Intensity of reflected sound wave now reduced (1) Difference between intensity of incident sound and reflected sound now greater (1) (Hence resultant intensity greater) Page 18

19 006 AH Physics λ x 11(a)(i) d l 8 diagram similar s or λ d = l x d = λl x (a) (ii) d = = m 1 (b) (i) d = λ 4n = = m (1) (b) (ii) n MgF < n Liquid no phase change at this surface constructive interference more light reflected (b) (Path length) in oil depends on angle of incidence or thickness different colours are seen due to interference 1 [END OF MARKING INSTRUCTIONS] Page 19

2005 Physics. Advanced Higher. Finalised Marking Instructions

2005 Physics. Advanced Higher. Finalised Marking Instructions 005 Physics Advanced Higher Finalised Marking Instructions These Marking Instructions have been prepared by Examination Teams for use by SQA Appointed Markers when marking External Course Assessments.