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Cambridge International AS & A Level
PHYSICS 9702/11
Paper 1 Multiple Choice October/November 2020
MARK SCHEME
Maximum Mark: 40
Published
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the
examination.
Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for
Teachers.
Cambridge International will not enter into discussions about these mark schemes.
Cambridge International is publishing the mark schemes for the October/November 2020 series for most
Cambridge IGCSE™
, Cambridge International A and AS Level and Cambridge Pre-U components, and some
Cambridge O Level components.

9702/11 Cambridge International AS & A Level – Mark Scheme
PUBLISHED
October/November
2020
© UCLES 2020 Page 2 of 3
Question Answer Marks
1 C 1
2 B 1
3 A 1
4 D 1
5 D 1
6 D 1
7 B 1
8 C 1
9 B 1
10 B 1
11 B 1
12 B 1
13 D 1
14 D 1
15 B 1
16 C 1
17 A 1
18 B 1
19 C 1
20 C 1
21 C 1
22 B 1
23 C 1
24 A 1
25 C 1
26 A 1
27 A 1

PUBLISHED
October/November
2020
28 A 1
29 B 1
30 A 1
31 A 1
32 A 1
33 D 1
34 A 1
35 B 1
36 B 1
37 A 1
38 D 1
39 A 1
40 A 1

PHYSICS 9702/12
MARK SCHEME
Maximum Mark: 40
Published
examination.
Teachers.
Cambridge IGCSE™

PUBLISHED
October/November
2020
1 B 1
2 C 1
3 A 1
4 D 1
5 B 1
6 A 1
7 A 1
8 D 1
9 B 1
10 C 1
11 C 1
12 A 1
13 A 1
14 C 1
15 B 1
16 A 1
17 D 1
18 C 1
19 A 1
20 C 1
21 C 1
22 D 1
23 D 1
24 B 1
25 C 1
26 A 1
27 A 1

PUBLISHED
October/November
2020
28 B 1
29 C 1
30 B 1
31 B 1
32 B 1
33 A 1
34 B 1
35 D 1
36 B 1
37 D 1
38 D 1
39 C 1
40 D 1

PHYSICS 9702/13
MARK SCHEME
Maximum Mark: 40
Published
examination.
Teachers.
Cambridge IGCSE™

PUBLISHED
October/November
2020
1 B 1
2 A 1
3 B 1
4 A 1
5 C 1
6 A 1
7 C 1
8 B 1
9 D 1
10 D 1
11 A 1
12 B 1
13 B 1
14 D 1
15 D 1
16 B 1
17 C 1
18 A 1
19 B 1
20 C 1
21 C 1
22 D 1
23 B 1
24 B 1
25 A 1
26 D 1
27 B 1

PUBLISHED
October/November
2020
28 C 1
29 A 1
30 C 1
31 D 1
32 D 1
33 B 1
34 A 1
35 C 1
36 C 1
37 D 1
38 C 1
39 D 1
40 B 1

PHYSICS 9702/21
Paper 2 AS Level Structured Questions October/November 2020
MARK SCHEME
Maximum Mark: 60
Published
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.
Teachers.
Cambridge IGCSE™

PUBLISHED
October/November 2020
Generic Marking Principles
These general marking principles must be applied by all examiners when marking candidate answers. They should be applied alongside the
specific content of the mark scheme or generic level descriptors for a question. Each question paper and mark scheme will also comply with these
marking principles.
GENERIC MARKING PRINCIPLE 1:
Marks must be awarded in line with:
• the specific content of the mark scheme or the generic level descriptors for the question
• the specific skills defined in the mark scheme or in the generic level descriptors for the question
• the standard of response required by a candidate as exemplified by the standardisation scripts.
Marks awarded are always whole marks (not half marks, or other fractions).
Marks must be awarded positively:
• marks are awarded for correct/valid answers, as defined in the mark scheme. However, credit is given for valid answers which go beyond the
scope of the syllabus and mark scheme, referring to your Team Leader as appropriate
• marks are awarded when candidates clearly demonstrate what they know and can do
• marks are not deducted for errors
• marks are not deducted for omissions
• answers should only be judged on the quality of spelling, punctuation and grammar when these features are specifically assessed by the
question as indicated by the mark scheme. The meaning, however, should be unambiguous.
Rules must be applied consistently, e.g. in situations where candidates have not followed instructions or in the application of generic level
descriptors.

PUBLISHED
Marks should be awarded using the full range of marks defined in the mark scheme for the question (however; the use of the full mark range may
be limited according to the quality of the candidate responses seen).
Marks awarded are based solely on the requirements as defined in the mark scheme. Marks should not be awarded with grade thresholds or
grade descriptors in mind.
Science-Specific Marking Principles
1 Examiners should consider the context and scientific use of any keywords when awarding marks. Although keywords may be present, marks
should not be awarded if the keywords are used incorrectly.
2 The examiner should not choose between contradictory statements given in the same question part, and credit should not be awarded for
any correct statement that is contradicted within the same question part. Wrong science that is irrelevant to the question should be ignored.
3 Although spellings do not have to be correct, spellings of syllabus terms must allow for clear and unambiguous separation from other
syllabus terms with which they may be confused (e.g. ethane / ethene, glucagon / glycogen, refraction / reflection).
4 The error carried forward (ecf) principle should be applied, where appropriate. If an incorrect answer is subsequently used in a scientifically
correct way, the candidate should be awarded these subsequent marking points. Further guidance will be included in the mark scheme
where necessary and any exceptions to this general principle will be noted.
5 ‘List rule’ guidance
For questions that require n responses (e.g. State two reasons …):
• The response should be read as continuous prose, even when numbered answer spaces are provided.
• Any response marked ignore in the mark scheme should not count towards n.
• Incorrect responses should not be awarded credit but will still count towards n.
• Read the entire response to check for any responses that contradict those that would otherwise be credited. Credit should not be
awarded for any responses that are contradicted within the rest of the response. Where two responses contradict one another, this
should be treated as a single incorrect response.
• Non-contradictory responses after the first n responses may be ignored even if they include incorrect science.

PUBLISHED
6 Calculation specific guidance
Correct answers to calculations should be given full credit even if there is no working or incorrect working, unless the question states ‘show
your working’.
For questions in which the number of significant figures required is not stated, credit should be awarded for correct answers when rounded
by the examiner to the number of significant figures given in the mark scheme. This may not apply to measured values.
For answers given in standard form (e.g. a × 10n) in which the convention of restricting the value of the coefficient (a) to a value between 1
and 10 is not followed, credit may still be awarded if the answer can be converted to the answer given in the mark scheme.
Unless a separate mark is given for a unit, a missing or incorrect unit will normally mean that the final calculation mark is not awarded.
Exceptions to this general principle will be noted in the mark scheme.
7 Guidance for chemical equations
Multiples / fractions of coefficients used in chemical equations are acceptable unless stated otherwise in the mark scheme.
State symbols given in an equation should be ignored unless asked for in the question or stated otherwise in the mark scheme.
Abbreviations
/ Alternative and acceptable answers for the same marking point.
( ) Bracketed content indicates words which do not need to be explicitly seen to gain credit but which indicate the context for an answer. The
context does not need to be seen but if a context is given that is incorrect then the mark should not be awarded.
___ Underlined content must be present in answer to award the mark. This means either the exact word or another word that has the same
technical meaning.

PUBLISHED
Mark categories
B marks These are independent marks, which do not depend on other marks. For a B mark to be awarded, the point to which it refers must be
seen specifically in the candidate’s answer.
M marks These are method marks upon which A marks later depend. For an M mark to be awarded, the point to which it refers must be seen
specifically in the candidate’s answer. If a candidate is not awarded an M mark, then the later A mark cannot be awarded either.
C marks These are compensatory marks which can be awarded even if the points to which they refer are not written down by the candidate,
providing subsequent working gives evidence that they must have known them. For example, if an equation carries a C mark and the
candidate does not write down the actual equation but does correct working which shows the candidate knew the equation, then the C
mark is awarded.
If a correct answer is given to a numerical question, all of the preceding C marks are awarded automatically. It is only necessary to
consider each of the C marks in turn when the numerical answer is not correct.
A marks These are answer marks. They may depend on an M mark or allow a C mark to be awarded by implication.
Annotations
 Indicates the point at which a mark has been awarded.
X Indicates an incorrect answer or a point at which a decision is made not to award a mark.
XP Indicates a physically incorrect equation (‘incorrect physics’). No credit is given for substitution, or subsequent arithmetic, in a physically
incorrect equation.
ECF Indicates ‘error carried forward’. Answers to later numerical questions can always be awarded up to full credit provided they are
consistent with earlier incorrect answers. Within a section of a numerical question, ECF can be given after AE, TE and POT errors, but
not after XP.
AE Indicates an arithmetic error. Do not allow the mark where the error occurs. Then follow through the working/calculation giving full
subsequent ECF if there are no further errors.
POT Indicates a power of ten error. Do not allow the mark where the error occurs. Then follow through the working/calculation giving full

PUBLISHED
TE Indicates incorrect transcription of the correct data from the question, a graph, data sheet or a previous answer. For example, the value
of 1.6 × 10–19 has been written down as 6.1 × 10–19 or 1.6 × 1019.
Do not allow the mark where the error occurs. Then follow through the working/calculation giving full subsequent ECF if there are no
further errors.
SF Indicates that the correct answer is seen in the working but the final answer is incorrect as it is expressed to too few significant figures.
BOD Indicates that a mark is awarded where the candidate provides an answer that is not totally satisfactory, but the examiner feels that
sufficient work has been done (‘benefit of doubt’).
CON Indicates that a response is contradictory.
I Indicates parts of a response that have been seen but disregarded as irrelevant.
M0 Indicates where an A category mark has not been awarded due to the M category mark upon which it depends not having previously
been awarded.
^ Indicates where more is needed for a mark to be awarded (what is written is not wrong, but not enough). May also be used to annotate
a response space that has been left completely blank.
SEEN Indicates that a page has been seen.

PUBLISHED
1(a)(i) force × perpendicular distance (of line of action of force to the point) B1
1(a)(ii) units: kg m s–2 m
= kg m2 s–2
A1
1(b) W = ρVg or W = ρALg C1
A = 5.2 / (790 × 2.4 × 9.81)
(= 2.8 × 10–4 (m2))
C1
= 2.8 × 102 mm2 A1
1(c)(i) (component =) 5.2 sin 56° = 4.3 (N)
or
5.2 cos 34° = 4.3 (N)
A1
1(c)(ii) (T × 2.4) or (4.3 × 1.2) or (4.6 × 1.8) C1
(T × 2.4) + (4.3 × 1.2) = (4.6 × 1.8) C1
T = 1.3 N A1

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2(a) constant gradient B1
2(b) (displacement until 0.20 s =) ½ × 1.96 × 0.20 (= 0.196m)
or
(displacement after 0.20 s =) ½ × 6.86 × 0.70 (= 2.401m)
C1
height = 2.401 – 0.196 C1
= 2.2 m
(alternative methods are possible using equations of uniformly accelerated motion)
A1
2(c) (Δ)E = mg(Δ)h or W(Δ)h C1
(Δ)E = 0.86 × 2.2
= 1.9 J
A1
2(d) curved line from the origin M1
gradient of curved line decreases and is zero at t = 0.20 s only A1
2(e) acceleration (of free fall) is unchanged/is not dependent on mass and (so) no effect B1

PUBLISHED
3(a) (force =) rate of change of momentum B1
3(b)(i) E = ½mv2 or ½ × 0.062 × 3.82 or ½ × 0.062 × 1.72 C1
loss of KE = ½ × 0.062 × (3.82 – 1.72)
= 0.36 J
A1
3(b)(ii) p = mv or 0.062 × 3.8 or 0.062 × 1.7 C1
change in momentum = 0.062 × (1.7 + 3.8)
= 0.34 N s
A1
3(b)(iii) (average resultant force =) 0.34 / 0.081 = 4.2 (N)
or
(average resultant force =) 0.062 × (1.7 + 3.8) / 0.081 = 4.2 (N)
A1
3(b)(iv) 1. average force = 4.2 + (0.062 × 9.81)
= 4.8 N
A1
2. average force = 4.8 N A1

PUBLISHED
4(a)(i) (stress =) force / cross-sectional area B1
4(a)(ii) (strain =) extension / original length B1
4(b)(i) E = FL / Ax C1
= GL / A A1
4(b)(ii) straight line from origin above the original line M1
line ends at point (4 small squares, F1). A1
4(b)(iii) 1. shaded area below the graph line and between the two vertical dashed lines B1
2. remove the force/F/F2 and the wire goes back to original length/zero extension B1
4(b)(iv) values have a large range B1
5(a) v = λ / T
or
v = fλ and f = 1 / T
C1
v = 8.0 × 10–2 / 0.40
= 0.20 m s–1
A1
5(b) I ∝ A2 C1
ratio = 22 / 42 C1
= 0.25 A1

PUBLISHED
6(a) the waves (of the same type) move in opposite directions and overlap B1
the waves have the same (speed and) frequency/wavelength B1
6(b)(i) zero amplitude B1
6(b)(ii) distance = 6.0 × 4
= 24 cm
A1
6(b)(iii) 180° A1
7(a) volt / ampere B1
7(b) R = ρL / A C1
A = 460 × 10–9 × 2.5 / 3.2 C1
= 3.6 × 10–7 m2 A1
7(c)(i) energy is dissipated in the internal resistance/r B1
7(c)(ii) E = IR + Ir or E = I (R + r) B1
7(c)(iii) P = I2R or P = I2r C1
I = E / 2r
(so) P = E2 / 4r
A1

PUBLISHED
8(a) similarity: same/equal mass
or
same/equal (magnitude of) charge
or
both fundamental (particles)
B1
difference: opposite (sign of) charge
or
one is matter and the other is antimatter
B1
8(b)(i) number of protons = 13 and number of neutrons = 12 A1
8(b)(ii) (charge =) 13 × 1.60 × 10–19 (C) = 2.1 × 10–18 (C) A1
8(c) force = 11 × 103 × 2.1 × 10–18 C1
work done = 11 × 103 × 2.1 × 10–18 × 0.04 C1
= 9.2 × 10–16 J A1

PHYSICS 9702/22
MARK SCHEME
Maximum Mark: 60
Published
Teachers.
Cambridge IGCSE™

PUBLISHED
marking principles.
descriptors.

PUBLISHED
2 The examiner should not choose between contradictory statements given in the same question part, and credit should not be awarded for any
correct statement that is contradicted within the same question part. Wrong science that is irrelevant to the question should be ignored.
3 Although spellings do not have to be correct, spellings of syllabus terms must allow for clear and unambiguous separation from other syllabus
terms with which they may be confused (e.g. ethane / ethene, glucagon / glycogen, refraction / reflection).
correct way, the candidate should be awarded these subsequent marking points. Further guidance will be included in the mark scheme where
necessary and any exceptions to this general principle will be noted.

PUBLISHED
your working’.
For questions in which the number of significant figures required is not stated, credit should be awarded for correct answers when rounded by
the examiner to the number of significant figures given in the mark scheme. This may not apply to measured values.
Abbreviations
technical meaning.

PUBLISHED
Mark categories
mark is awarded.
Annotations
incorrect equation.
not after XP.

PUBLISHED
further errors.
been awarded.

PUBLISHED
1(a) density and temperature indicated as scalars B1
acceleration and momentum indicated as vectors B1
1(b)(i) decelerates
or
speed/velocity decreases
B1
1(b)(ii) speed = (Δ)d / (Δ)t or gradient C1
= e.g. (0.56 – 0.20) / 1.5
= 0.24 ms–1
A1
1(c) displacement is zero (so) average velocity is zero B1
2(a)(i) (Δ)p = ρg(Δ)h
520 = 1000 × 9.81 × h
C1
h = 0.053 m A1
2(a)(ii) (upthrust =) (Δ)p × A
= (Δ)p × π(d / 2)2 or (Δ)p × πr 2
C1
= 520 × π(0.031 / 2)2 = 0.39 (N) A1
2(a)(iii) T = 0.84 – 0.39
= 0.45 N
A1

PUBLISHED
2(b)(i) a = (v – u) / t or (Δ)v / (∆)t or gradient C1
= e.g. 8.0 × 10–2 / 2.0
= 4.0 × 10–2 m s–2
A1
2(b)(ii) distance = (½ × 2.5 × 0.10) + (½ × 1.5 × 0.10) or (½ × 4.0 × 0.10)
(= 0.20 (m))
C1
depth = 0.32 – 0.20
= 0.12 m
A1
2(c)(i) viscous (force) B1
2(c)(ii) viscous force increases (with speed/time/depth) B1
(so) acceleration decreases B1

PUBLISHED
3(a)(i) F = kx C1
F1 = 800 × 0.045
= 36 N
A1
3(a)(ii) (E =) ½kx2 or ½Fx or area under graph C1
½ × 800 × (0.045)2 or ½ × 36 × 0.045 = 0.81 (J) A1
3(b)(i) efficiency = (0.72 / 0.81) × 100
= 89%
A1
3(b)(ii) E = ½mv2 C1
p = mv C1
0.72 = ½ × 0.020 × v2 and p = 0.020 × v
p = 0.17 N s
A1
3(c)(i) (Δ)E = mg(Δ)h C1
h = 0.60 / (0.020 × 9.81) = 3.1 m A1
3(c)(ii) F = (0.72 – 0.60) / 3.1 C1
= 0.039 N A1
3(c)(iii) resultant force on ball is less (than that with air resistance) so time (taken) is more (than T) B1

PUBLISHED
4(a) (component =) 96 sin 38° = 59 (N)
or
96 cos 52° = 59 (N)
A1
4(b) (45 × 2.9) or (T × 1.8) or (59 × 1.5) C1
(45 × 2.9) = (T × 1.8) + (59 × 1.5) C1
T = 23 N A1
5(a) v = fλ or c = fλ C1
f = 3.0 × 108 / 0.040 C1
= 7.5 × 109 (Hz)
= 7.5 GHz
A1
5(b)(i) path difference = 0.020 m A1
5(b)(ii) phase difference = 180° A1
5(c) (intensity) increases C1
(intensity) increases by a factor of 4 A1
5(d)(i) minimum moves closer to the maximum
or
decrease in separation of maximum and minimum
B1
5(d)(ii) the maximum and minimum exchange places
or
the maximum becomes a minimum and the minimum becomes a maximum
B1

PUBLISHED
6(a) I = I1 + I2 + I3 B1
(V / R) = (V / R1) + (V / R2) + (V / R3) or (I / V) = (I1 / V) + (I2 / V) + (I3 / V)
and
1 / R = 1 / R1 + 1 / R2 + 1 / R3
B1
6(b)(i) current = 0.49 + 0.45
= 0.94 A
A1
6(b)(ii) 8.0 = (0.94 × r) + (0.45 × 16) C1
r = 0.85 Ω A1
6(c) I = Anvq
v = (0.45 / 0.49) × 2.1 × 10–4
C1
= 1.9 × 10–4 m s–1 A1
6(d) total/combined resistance decreases B1
(current in battery increases so terminal) potential differencedecreases B1

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7(a) similarity: same/equal mass
or
same/equal (magnitude of) charge
or
both fundamental (particles)
B1
difference: opposite (sign of) charge
or
one is matter and the other is antimatter
B1
7(b)(i) arrow points to the right B1
7(b)(ii) (electric) field strength increases
or
(electric) force increases
B1
acceleration increases B1
7(b)(iii) force (on α-particle) has twice the magnitude (of force on electron) B1
force (on α-particle) is in opposite direction (to force on electron) B1

PHYSICS 9702/23
MARK SCHEME
Maximum Mark: 60
Published
Teachers.
Cambridge IGCSE™

PUBLISHED
marking principles.
descriptors.

PUBLISHED

PUBLISHED
your working’.
Abbreviations
technical meaning.

PUBLISHED
Mark categories
mark is awarded.
Annotations
incorrect equation.
not after XP.

PUBLISHED
further errors.
been awarded.

PUBLISHED
1(a)(i) wavelength = 8.5 × 10–5 m A1
1(a)(ii) f = v / λ or c / λ C1
= 3.0 × 108 / 8.5 × 10–5 (= 3.5 × 1012)
= 3.5 THz
A1
1(a)(iii) infrared B1
1(b) (implied) percentage uncertainty in I = 4%
or
(implied) fractional uncertainty in I = 0.04
C1
percentage uncertainty in E = 5% + (4% × 2)
= 13%
A1

PUBLISHED
2(a) point where (all) the weight (of the body) M1
is considered/seems to act A1
2(b)(i) horizontal component of force = 38 cos 60° or 38 sin 30°
= 19 N
A1
2(b)(ii) (T × 1.2) or (19 × 0.9) or 17 C1
(T × 1.2) = (19 × 0.9)
T = 14 N
A1
2(b)(iii) F = 45 + 38 sin 60°
= 78 N
A1

PUBLISHED
3(a) s = ½at 2 C1
57 = ½ × 9.81 × t2 and t = 3.4 (s) A1
3(b) horizontal distance = 41 × 3.4
= 140 m
A1
3(c) (displacement)2 = 572 + 1402 C1
displacement = ( 572 + 1402)0.5
= 150 m
A1
3(d) straight line from the origin with positive gradient B1
3(e) (1480 – m) × 0.340 = m × 41.0 C1
m = 12.2 kg A1
or
mc 0.34 = mb 41 and mc + mb = 1480 (C1)
mc = (41 / 0.34)mb
(41 / 0.34)mb + mb = 1480
mb = 12.2 kg
(A1)
3(f) acceleration (of free fall) is unchanged/is not dependent on mass M1
(so) no change (to the graph) A1

PUBLISHED
4(a) compression/extension is proportional to force (provided limit of proportionality is not exceeded) B1
4(b) (E) = ½Fx or ½kx2 or area under graph C1
= ½ × 8 × 16 × 10–2 = 0.64 (J)
or
= ½ × 50 × (16 × 10–2)2 = 0.64 (J)
A1
4(c)(i) (E) = ½mv2 C1
0.64 = ½ × 0.076 × v2
v = 4.1 m s–1
A1
4(c)(ii) (Δ)(E) = mg(Δ)h C1
= 0.076 × 9.81 × 0.24
(= 0.18 (J))
C1
kinetic energy = 0.64 – 0.18
= 0.46 J
A1
4(c)(iii) v = 4.1 m s–1 A1
4(d) W = Fs C1
d = 0.30 + (2π × 0.12) + 0.25 (= 1.3m) C1
F = 0.23 / 1.3
= 0.18 N
A1

PUBLISHED
5(a)(i) T = 2.0 × 10–5 × 6.0 (= 1.2 × 10–4 s) C1
f = 1 / (2.0 × 10–5 × 6.0)
= 8300 Hz
A1
5(a)(ii) new trace shows the same period B1
new trace shows amplitude of 10 small squares B1
5(a)(iii) (trace is a) vertical line B1
5(b)(i) nλ = d sinθ C1
λ = (3.4 × 10–6 × sin 16°) / 2
= 4.7 × 10–7 m
A1
5(b)(ii) n = 3.4 × 10–6 (× sin 90°) / 4.7 × 10–7 or 2 (× sin 90°) / sin 16°
(= 7.2 or 7.3)
C1
highest order = 7 A1

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6(a) ( ) ( )
work done /energy transferred from electrical to other forms
charge
B1
6(b) R = ρL / A B1
V = LA and (so) R = ρV / A2 (with ρ and V constant) B1
6(c) E = IR + Ir or E = I(R + r) or E – Ir = IR
and
R = (E / I) – r
A1
6(d)(i) P = I2R or P = IV or P = V2 / R C1
R = 5.4 (Ω) or V = 10.8 (V) C1
P = 2.02 × 5.4
= 22 W
A1
6(d)(ii) 1. r = 0.60 Ω A1
2. E = gradient C1
= e.g. 5.4 / 0.45
= 12 V
A1

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7(a)(i) electric field strength = V / d B1
7(a)(ii) force = Vq / d B1
7(a)(iii) kinetic energy = Vq B1
7(b)(i) no change B1
7(b)(ii) no change B1
7(c)(i) nucleon number = 14
and
proton number = 7
A1
7(c)(ii) (electron) antineutrino B1

PHYSICS 9702/31
Paper 3 Advanced Practical Skills 1 October/November 2020
MARK SCHEME
Maximum Mark: 40
Published
Teachers.
Cambridge IGCSE™

PUBLISHED
marking principles.
descriptors.

PUBLISHED

PUBLISHED
your working’.

PUBLISHED
1(a) Value(s) of p in the range 9.0–15.0 cm with unit. 1
1(b) Value of m in the range 10.0–14.0 g. 1
1(c) Six sets of readings of m (different values) and p with correct trend and without help from the Supervisor scores 5
marks, five sets scores 4 marks, etc.
5
Range: Δm ⩾ 80 g. 1
Column headings:
Each column heading must contain a quantity, a unit and a separating mark where appropriate.
The presentation of quantity and unit must conform to accepted scientific convention, e.g. m / g, p / m½.
1
Consistency:
All values of p must be given to the nearest mm.
1
Significant figures:
All values of m must be given to the same number of significant figures as, or one greater than, the number of s.f. of
the m values as recorded in table.
1
Calculation: Values of p are correct. 1

PUBLISHED
1(d)(i) Axes:
Sensible scales must be used, no awkward scales (e.g. 3:10 or fractions).
Scales must be chosen so that the plotted points occupy at least half the graph grid in both x and y directions.
Scales must be labelled with the quantity that is being plotted.
Scale markings should be no more than three large squares apart.
1
Plotting of points:
All observations in the table must be plotted on the grid.
Diameter of plotted points must be ⩽ half a small square.
Points must be plotted to an accuracy of half a small square.
1
Quality:
All points in the table must be plotted on the grid.
Trend of points must be correct.
It must be possible to draw a straight line that is within ±0.1 on the p axis of all plotted points.
1
1(d)(ii) Line of best fit:
Judge by balance of all points on the grid about the candidate’s line (at least 5 points). There must be an even
distribution of points either side of the line along the full length.
Allow one anomalous point only if clearly indicated (i.e. circled or labelled) by the candidate. There must be at least five
points left after the anomalous point is disregarded.
Lines must not be kinked or thicker than half a small square.
1

PUBLISHED
1(d)(iii) Gradient:
The hypotenuse of the triangle used must be greater than half the length of the drawn line.
Method of calculation must be correct, e.g. not Δx / Δy.
Gradient sign on answer line matches graph drawn.
Both read-offs must be accurate to half a small square in both the x and y directions.
1
y-intercept:
Correct read-off from a point on the line substituted correctly into y = mx + c or an equivalent expression.
Read-off accurate to half a small square in both x and y directions.
or
Intercept read directly from the graph, with read-off at x = zero, accurate to half a small square.
1
1(e) Value of A = candidate’s gradient and value of B = candidate’s intercept.
The values must not be fractions.
1
Unit for A correct (e.g. cm0.5 g–0.5 or cm½ g–½) and unit for B correct (e.g. cm0.5 or cm½). 1

PUBLISHED
2(a)(i) Value(s) of raw θ to the nearest degree. 1
2(a)(ii) Correct calculation of sinθ. 1
2(a)(iii) Justification for significant figures in sinθ linked to s.f. in θ. 1
2(b)(i) Value of time t in range 0.5–3.0 s. 1
Evidence of repeat values of t. 1
2(b)(ii) Percentage uncertainty based on an absolute uncertainty in t in range 0.2–0.5 s.
If repeat readings have been taken, then the absolute uncertainty can be half the range (but not zero) if the working is
clearly shown.
Correct method of calculation to obtain percentage uncertainty.
1
2(c)(i) Second value of θ recorded. 1
Second value of θ less than 70.0°. 1
2(c)(ii) Second value of t recorded. 1
Second value of t greater than first value of t. 1
2(d)(i) Two values of k calculated correctly. The final k values must not be fractions. 1
2(d)(ii) Valid comment consistent with the calculated values of k, testing against a criterion stated by the candidate. 1

PUBLISHED
2(e)(i) A Two readings are not enough to draw a (valid) conclusion (not “not enough for accurate results”, “few readings”).
B Difficulty in measuring time t with a reason, e.g. time interval is short/percentage uncertainty is large/difficult to
release shape and start stop-watch simultaneously/difficult to judge when to stop timing.
C Difficulty linked to the practical set up of the board, e.g. holding with one clamp, board is not square to bench/board
is not stable/board tilts to side.
D Difficulty linked to release, e.g. force applied varies/starting position may vary/adhesive putty sticks (affects friction).
E Difficulty with the angle with reason, e.g. setting or adjusting the angle when changing the clamp/difficult to make
fine adjustments to the angle.
1 mark for each point up to a maximum of 4.
4
2(e)(ii) A Take more readings and plot a graph or take more readings and compare k values (not “repeat readings” on its
own).
B Improved method to measure t, e.g. timer and pressure/contact switch at release point and/or at bottom
or video with timer/frame-by-frame.
C Improved method to support board, e.g. use more than one clamp/clamp both sides/support with a block.
D Improved method of release, e.g. use of a stop/use of a card gate.
E Improved method to make fine adjustments to angle, e.g. scissor jack/use of screw thread on a clamp.
4

PHYSICS 9702/33
MARK SCHEME
Maximum Mark: 40
Published
Teachers.
Cambridge IGCSE™

PUBLISHED
marking principles.
descriptors.

PUBLISHED

PUBLISHED
your working’.

PUBLISHED
1(a) Values of raw diameter either all recorded to 0.01 cm or all to 0.001 cm and final value in range 1.00–10.00 cm. 1
Evidence of repeat measurements. 1
1(b) p in range 15.0 cm ⩽ p ⩽ 19.0 cm and F in range 1.0 N ⩽ F ⩽ 5.0 N. 1
1(c) Six (or more) sets of readings of p and F (different values of non-zero p) with the correct trend and without help from the
Supervisor scores 3 marks, five sets scores 2 marks, etc.
3
Range: Must include values of p ⩽ 8.0 cm and p ⩾ 42.0 cm. 1
Column headings:
The presentation of quantity and unit must conform to accepted scientific convention e.g. (p + r) / cm
1
Consistency:
All raw values of p must be given to the nearest 0.1 cm.
1
Consistency:
All raw values of F must be given to the nearest 0.1 N.
1
Calculation: Values of (p + r) are correct. 1

PUBLISHED
1(d)(i) Axes:
1
Plotting of points:
1
Quality:
All points in the table (at least 5) must be plotted on the grid.
It must be possible to draw a straight line that is within ±0.20 N (to scale) on the F axis (normally y-axis) of all plotted
points.
1
Allow one anomalous point only if clearly indicated by the candidate. There must be at least five points left after the
anomalous point is disregarded.
1
1(d)(iii) Gradient:
1
y-intercept:
or
Intercept read directly from the graph, with read-off at p + r = zero, accurate to half a small square.
1

PUBLISHED
1(e) 3.00
gradient gradient
W
Q = =
1
3.00 -intercept
-intercept
gradient
y
S Q y
×
= × =
1
Units for Q and S correct (e.g. m and N m). 1

PUBLISHED
2(a)(i) Raw L to the nearest 0.1 cm and final value in the range 11.5–12.5 cm. 1
2(a)(ii) Percentage uncertainty based on an absolute uncertainty ΔL in the range 2–5 mm.
If repeat readings have been taken, then the absolute uncertainty can be half the range (but not zero) if the working is
clearly shown.
1
2(b)(i) All raw times measured either to the nearest 0.1 s or all to the nearest 0.01 s. 1
Evidence of measurement of nT repeated where n ⩾ 5. 1
Value of T in the range 0.5 s ⩽ T ⩽ 1.0 s. 1
2(b)(ii) Calculation of T2 correct. 1
2(b)(iii) Justification of the number of significant figures in terms of the number of s.f. in (raw) time only. 1
2(c) Second values of L and T. 1
Second value of T < first value of T. 1
2(e) Correct calculation of g using candidate’s second k and in range 2.0 ms–2 ⩽ g ⩽ 20.0 ms–2. 1

PUBLISHED
2(f)(i) A Two readings are not enough to draw a (valid) conclusion (not “not enough for accurate results”, “few readings”).
B Difficulty in measuring time or T with a reason, e.g. judging when to start or stop the stop-watch, judging
start/end/complete oscillation.
C Difficulty in measuring L with a reason, e.g. wire is not straight/is kinked/has rounded corners.
D Corners are not at right angles
or
square not complete/joined
or
shape changes when suspended/during oscillation.
E Oscillations are not in one plane
or
square catches on drawing pin.
4
2(f)(ii) A Take more readings and plot a graph or take more readings and compare k values (not “repeat readings” on its
own).
B Method of improving time or T, e.g. fiducial marker at centre/video (or record or film) and timer (or frame-by-
frame)/place a grid behind the apparatus.
C Method of improving L, e.g. use thicker/stiffer wire or use a former/shaping block.
D Method of improving the setting of 90° corners, e.g. use a set square or protractor with appropriate reason
or
method of fixing ends, e.g. use adhesive putty/tape with appropriate reason.
E Method of improving oscillation, e.g. longer pin/use of guide with detail/groove in pin/use a nail/use a hook.
4

PHYSICS 9702/34
MARK SCHEME
Maximum Mark: 40
Published
Teachers.
Cambridge IGCSE™

PUBLISHED
marking principles.
descriptors.

PUBLISHED
awarded for any responses that are contradicted within the rest of the response. Where two responses contradict one another, this should
be treated as a single incorrect response.

PUBLISHED
your working’.

PUBLISHED
1(a) Value of raw x to the nearest mm and final value in range 38.0–42.0 cm. 1
1(b) Value of θ in range 60°–100°. 1
1(c) Six (or more) sets of readings of x and θ with correct trend and without help from the Supervisor scores 5 marks, five sets
scores 4 marks etc.
Values of x should be different and non-zero.
5
Range: xmin ⩽ 20.0 cm and xmax ⩾ 45.0 cm. 1
Column headings:
Each column heading must contain a quantity, a separating mark and a unit where appropriate.
Heading for cosθ must have no unit.
The presentation of quantity and unit must conform to accepted scientific convention e.g. x / cm.
1
Consistency:
All values of raw θ must be given to the nearest degree.
1
Values of cosθ should be to the same number of s.f. as (or one more than) the number of s.f. in the corresponding value of θ.
1
Calculation:
Values of cosθ calculated correctly.
1

PUBLISHED
1(d)(i) Axes:
1
Plotting of points:
All observations must be plotted on the grid.
Plots must be accurate to within half a small square in both x and y directions.
1
Quality:
All points in the table must be plotted (at least 5) for this mark to be awarded.
Trend of points should be correct.
Scatter of plotted points must be no more than ±0.05 from a straight line on the cosθ axis.
1
Judged by balance of all points on the grid (at least 5) about the candidate’s line. There must be an even distribution of points
either side of the line along the full length.
One anomalous point is allowed only if clearly indicated (i.e. circled or labelled) by the candidate.
Lines must not be kinked or thicker than half a square.
1
1(d)(iii) Gradient:
The sign of the gradient must match the graph drawn.
1
y-intercept:
Correct read-off from a point on the line substituted into y = mx + c or an equivalent expression.
or
Intercept read directly from the graph, with read-off at x = zero accurate to half a small square in y direction.
1

PUBLISHED
1(e) a equal to candidate’s gradient and b equal to candidate’s intercept. Values must not be written as fractions. 1
Unit for a correct (e.g. cm–1) and consistent with value and no unit given for b. 1
2(a)(i) Value of raw x to nearest mm and final value in range 20–24 mm with unit. 1
2(a)(ii) Values of raw D and d to nearest mm and final value of D in the range 38–42 mm. 1
2(a)(iii) Correct calculation of L. 1
2(a)(iv) Justification based on significant figures in x, D and (D – d). 1
2(b)(i) Raw values of times all to 0.1 s or all to 0.01 s and value of T in range 0.5–2.5 s. 1
Evidence of repeats: at least two values of time. 1
2(b)(ii) Percentage uncertainty based on an absolute uncertainty in time value of 0.2–0.5 s.
If repeat readings have been taken, then the absolute uncertainty can be half the range (but not zero) if the working is clearly
shown.
1
2(c) Second values of x and T. 1
Quality: second T > first T. 1
2(d)(i) Two values of k calculated correctly. The final values of k must not be fractions. 1
2(d)(ii) Valid comment relating to the calculated values of k, testing against a criterion specified by the candidate. 1
2(e) Correct calculation of g. 1

PUBLISHED
2(f)(i) A Two readings are not enough to draw a (valid) conclusion (not “not enough for accurate results”, “few readings”).
B Difficult to measure diameters or x with reason e.g. parallax/zero not at end of ruler/x varies around roller/nuts or bolt
prevent placement of ruler.
C θ small so large uncertainty/large % uncertainty in θ.
D Oscillations die away quickly.
E Difficult to measure time/T because it is difficult to judge the end/beginning/completion of an oscillation.
F Roller slips down board.
4
2(f)(ii) A Take more readings and plot a graph or take more readings and compare k values (not “repeat readings” on its own).
B Use metre rule/calipers/micrometer/blocks either side of washer/use pointers with detail.
C Method to reduce uncertainty in θ e.g. use of trigonometry with detail/increase θ.
D Method to increase the number of oscillations e.g. smoother board/named smooth material for board/sand board.
E Method of improving timing e.g. fiducial marker at centre of oscillation or video/record/film with timer/frame-by-frame.
F Method of reducing slipping e.g. rougher/named higher friction surface/smaller θ.
4

PHYSICS 9702/35
MARK SCHEME
Maximum Mark: 40
Published
Teachers.
Cambridge IGCSE™

PUBLISHED
marking principles.
descriptors.

PUBLISHED

PUBLISHED
your working’.

PUBLISHED
1(a) Value of I with unit in the range 30.0–50.0 mA. 1
1(b) Six (or more) sets of readings of R and I (different values of R) with the correct trend and without help from the
Supervisor scores 5 marks, five sets scores 4 marks, etc.
5
Range:
Must use R = 204 Ω and 22.7 Ω.
1
Column headings:
The presentation of quantity and unit must conform to accepted scientific convention, e.g. 1/I (mA–1
).
1
Consistency of presentation:
All raw values of I must be given to 0.1 mA or all to 0.01 mA.
1
All values of 1/I must be given to the same number of s.f. as (or one more than) the number of s.f. in raw I.
1
Calculation: Values of 1/I are correct. 1
1(c)(i) Axes:
1
Plotting of points:
1
Quality:
All points in the table must be plotted (at least 5) on the grid for this mark to be awarded.
It must be possible to draw a straight line that is within ±4 Ω (to scale) on the R axis (normally x-axis) of all plotted
points.
1

PUBLISHED
1(c)(ii) Line of best fit:
Allow one anomalous point only if clearly indicated (i.e. circled or labelled) by the candidate. There must be at least five
points left after the anomalous point is disregarded.
1
1(c)(iii) Gradient:
1
y-intercept:
or
Intercept read directly from the graph, with read-off at R = zero, accurate to half a small square.
1
1(d) E = 1 / gradient 1
X = E × y-intercept
or
X = y-intercept / gradient
1
Units for E and X correct (e.g. V and Ω). 1

PUBLISHED
2(a)(i) p = 7.0 ± 0.2 cm
q = 21.0 ± 0.2 cm
w = 24.0 ± 0.2 cm
1
All raw values recorded to the nearest millimetre. 1
2(a)(ii)
Correct calculation of
2q
p q
+
.
1
2(b)(i) Value of d. 1
2(b)(ii) Percentage uncertainty based on an absolute uncertainty Δd in the range 2–5 mm.
If repeated readings have been taken, then the absolute uncertainty can be half the range (but not zero) if working is
clearly shown.
1
2(b)(iii) Value of (w – d) correctly calculated from w and d. 1
2(c)(i) Valid method, e.g. measure q / 2 in several places and draw a straight line with a ruler. 1
2(c)(ii) Second q recorded to the nearest mm and half original value of q ± 1 mm. 1
2(c)(iii) Second value of d recorded. 1
Second value of d is larger than first value of d. 1

PUBLISHED
2(e)(i) A Two readings are not enough to draw a (valid) conclusion (not “not enough for accurate results”, “few readings”).
B Difficult to judge when top edge of card is horizontal/difficult to keep card horizontal.
C Difficult to accurately locate the centre of the paper clip, e.g. clip too large/clip not vertical/sides of clip not straight.
D Difficulty with the attachment, e.g. paper clip does not grip/card falls.
E Difficult to measure d with reason, e.g. touching disturbs equilibrium/ruler held by hand in mid-air/parallax error.
F Card bends easily
or
corners on card may not be at right angles.
4
2(e)(ii) A Take more readings and plot a graph or take more readings and compare k values (not “repeat readings” on its
own).
B Method to improve judgement of horizontal, e.g. use of spirit level/clamped ruler with detailed method to ensure
horizontal/place a grid behind the apparatus with method to ensure horizontal/turn off air conditioning.
C Method to improve location of centre of paper clip, e.g. use narrower paper clip/measure to either side of clip and
average/use calipers to measure width of clip.
D Improved method of suspension, e.g. place pin through card/hole with needle/add adhesive putty.
E Improved method to measure d, e.g. clamp ruler/write scale on card/carefully remove with paper clip and measure
on bench.
F Use of named more rigid material
or
detailed use of a set square or protractor.
4

PHYSICS 9702/36
MARK SCHEME
Maximum Mark: 40
Published
Teachers.
Cambridge IGCSE™

9702 w20 ms_all

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