Cambridge IGCSE™
0625/04
PHYSICS
For examination from 2023
Paper 4 Theory (Extended)
MARK SCHEME
Maximum Mark: 80
Specimen
This document has 12 pages. Any blank pages are indicated.
© UCLES 2020
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Cambridge IGCSE – Mark Scheme
SPECIMEN
For examination
from 2020
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 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.
© UCLES 2020
Page 2 of 12
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).
GENERIC MARKING PRINCIPLE 5:
Rules must be applied consistently, e.g. in situations where candidates have not followed instructions or in the application of generic level
descriptors.
GENERIC MARKING PRINCIPLE 4:
•
•
•
•
•
Marks must be awarded positively:
GENERIC MARKING PRINCIPLE 3:
Marks awarded are always whole marks (not half marks, or other fractions).
GENERIC MARKING PRINCIPLE 2:
•
•
•
Marks must be awarded in line with:
GENERIC MARKING PRINCIPLE 1:
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 Principles
0625/04
Cambridge IGCSE – Mark Scheme
SPECIMEN
For examination
from 2023
•
•
•
•
•
Page 3 of 12
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.
For questions that require n responses (e.g. State two reasons …):
‘List rule’ guidance
© UCLES 2020
5
4The 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.
3Although 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).
2The 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.
1Examiners 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.
Science-Specific Marking Principles
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.
GENERIC MARKING PRINCIPLE 6:
0625/04
Calculation specific guidance
Cambridge IGCSE – Mark Scheme
SPECIMEN
For examination
from 2020
Guidance for chemical equations
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.
These are answer marks. They may depend on an M mark or allow a C mark to be awarded by implication.
C marks
A marks
Page 4 of 12
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, the later A mark cannot be awarded either.
M marks
© UCLES 2020
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.
B marks
Mark categories
State symbols given in an equation should be ignored unless asked for in the question or stated otherwise in the mark scheme.
Multiples / fractions of coefficients used in chemical equations are acceptable unless stated otherwise in the mark scheme.
7
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.
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.
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.
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’.
6
0625/04
‘or words to that effect’
‘significant figures’ – answers are normally acceptable to any number of significant figures ⩾ 2. Any exceptions to this general
rule will be specified in the mark scheme.
o.w.t.t.e.
s.f.
© UCLES 2020
Page 5 of 12
Work which has been crossed out and not replaced but can easily be read, should be marked as if it had not been crossed
out.
‘error carried forward’
e.c.f.
Crossed-out work
Indicates that something which is not correct or irrelevant is to be disregarded.
Ignore / Ig
Only accept these where specified in the mark scheme.
A less than ideal answer which should be marked correct.
Accept / Acc
Fractions
Indicates that an incorrect answer is not to be disregarded but cancels another otherwise correct alternative offered by the
candidate for this mark.
NOT / not
If the only error in arriving at a final answer is because given or previously calculated data has clearly been misread but used
correctly, all but the final A mark can be awarded.
Indicates alternative answers, any one of which is satisfactory for scoring the marks.
OR / or
Transcription errors
Statements on both sides of the AND are needed for that mark.
AND / and
If the only error in arriving at a final answer is clearly an arithmetic one, all but the final A mark can be awarded. Regard a
power of ten error as an arithmetic error.
The word or phrase in brackets is not required but sets the context.
(brackets)
Arithmetic errors
Actual word underlined must be used by candidate (grammatical variants accepted).
underline
For examination
from 2023
Alternative answers for the same marking point.
Cambridge IGCSE – Mark Scheme
SPECIMEN
/
Abbreviations and guidance
0625/04
© UCLES 2020
2(b)(iii)
2(b)(ii)
2(b)(i)
2(a)
Question
1(c)
1(b)
1(a)
Question
0625/04
Dt
Dv
OR calculation shown
a=
elastic (energy) OR strain (energy)
6000 N
6000 N
OR
Page 6 of 12
(v − u)
and F = ma or
t
0.046 # 65
or
0.00050
0.046 × 130 000
OR
B1
A1
C1
A1
3.0 kg m / s OR 3.0 N s
m (v − u)
3.0
or
t
0.00050
C1
(p =) mv OR 0.046 × 65
(F =)
B1
impulse
Marks
A1
C1
B1
Answer
1
1
× 40 × 10) OR × (30 + 20) × 40
2
2
force
1000 m
distance = (20 × 40) + (
C1
B1
less driving force OR greater resistive force / friction / air resistance / drag AND resultant force less
area under graph / area under line
B1
A1
C1
C1
Marks
For examination
from 2020
acceleration less / at a slower rate
acceleration in range 0.30 to 0.45 m / s2
α=
mention of gradient of graph at t = 30 s OR tangent drawn at t = 30 s and triangle drawn OR values of t and v taken from
graph
Answer
Cambridge IGCSE – Mark Scheme
SPECIMEN
© UCLES 2020
5(a)
Question
4(b)(ii)
4(b)(i)
4(a)
Question
B1
rate of collision (with walls of balloon) decreases OR fewer collisions per unit area
motion:
Ice: vibrate
Water: move (around) or slide over each other
arrangement:
Ice: in lattice / regular / arranged / orderly / fixed in place
Water: random / irregular / not arranged / not orderly
8.0 × 104 Pa
Page 7 of 12
Answer
B2
Marks
A1
C1
B1
fewer atoms per unit volume OR density of gas less
P1 V1
1.0 # 105 # 9.6
OR
V2
12
A1
force on wall = (total) rate of change of momentum (of atoms)
OR = change of momentum (of atoms) per second
OR = change of momentum (of atoms) / time
PV = constant OR P1V1 = P2V2 OR (P2 =)
C1
(atoms) undergo change of momentum
B2
any two disadvantages from: intermittent supply / unattractive / takes up space / uses land / d.c. output
B1
B2
any two advantages from: no polluting gases / quiet / low maintenance / can be placed on roofs / clean / cheap to run
3(c)
atoms collide with wall (and rebound) OR atoms rebound from wall
A1
renewable OR not (according answer) AND matching explanation
Marks
M1
any suitable resource, e.g. fossil fuels; hydroelectric; wave; wind NOT geothermal, nuclear
Answer
B1
small nuclei to larger nuclei OR hydrogen to helium (in some way) OR loss of mass
3(b)
B1
nuclei combine / join together
3(a)(ii)
B1
Marks
For examination
from 2023
nuclear fusion
Answer
Cambridge IGCSE – Mark Scheme
SPECIMEN
3(a)(i)
Question
0625/04
© UCLES 2020
7(c)
7(b)
7(a)
Question
6(b)
6(a)(ii)
6(a)(i)
Question
5(b)(ii)
5(b)(i)
Question
0625/04
m
B1
B1
B1
(display used to determine) time for echo of pulse to return from front AND back of bubble
use of speed of sound in the metal
use of distance = speed × time to calculate position and size
Page 8 of 12
B1
A1
C1
B1
use of transducer to send and receive pulses of ultrasound
Correct answer: e.g. 330 m / s gives 15 000 Hz
v = fλ OR (f =)
(a)
0.022
B1
emergent ray diverging away from the yellow ray AND outside of prism
OR
B1
refracted ray in prism below yellow ray AND above normal
v
B1
enlarged AND inverted AND real underlined
330–350 m / s
B1
any two of: enlarged / inverted / real underlined
Marks
A1
two correct rays traced back and image indicated
Answer
M2
any two rays that start at the top of the image from:
•
seems to come from F1 to lens and emerges paraxially
•
passes through centre of lens undeviated
•
paraxial to the lens and passes through F2
Marks
A1
3.0 × 108 (J)
Answer
C1
(∆E =) cm∆θ OR 2.1 × 103 × 41 000 × 3.5
C1
A1
m
in any form OR (m =) Vd OR 1800 × 0.025 × 920
V
Marks
For examination
from 2020
41 000 kg
d=
Answer
Cambridge IGCSE – Mark Scheme
SPECIMEN
© UCLES 2020
9(b)
9(a)
Question
8(b)
8(a)
Question
0625/04
1 1
d + n
12 6
1
A1
(V8 = 2 × 8 =) 16 V
B1
–ve(ly charged ball) attracted to +ve / repelled from –ve
B1
B1
particles: electrons
direction: from left to right (through ammeter)
Page 9 of 12
B1
ball gets –ve charge (from –ve plate)
Marks
C1
OR alternative route
supply V
24
OR =
OR = 2 (A)
I8 =
12
12
Answer
A1
(V8 =) 16 V
A1
C1
(6 # 12)
18
C1
8
8
V8 = supply V × d n OR = 24 × d n
12
12
OR (RP =)
RS RC
(RS + RC)
(RP =) 4.0 Ω
OR (RP =)
OR (RP =)
1
in any form
1
1 l
b
+
RS RC
C1
(RS =) 12 (Ω)
(RP =)
C1
Marks
For examination
from 2023
RS = RA + RB in any form OR (RS =) RA + RB OR (RS =) 4 + 8
Answer
Cambridge IGCSE – Mark Scheme
SPECIMEN
© UCLES 2020
11(b)
11(a)
Question
10(b)
10(a)(ii)
10(a)(i)
Question
9(c)
Question
0625/04
Q
words, numbers, symbols
t
B1
B1
B3
temperature of hydrogen increases AND a protostar is formed
nuclear fusion begins and outward force from this reaction balances inward force of gravity
any three from:
microwave radiation is observed at all points in space around the Earth o.w.t.t.e.
radiation was produced when the Universe was formed
this radiation has expanded into the microwave region of the electromagnetic spectrum
this is evidence that the Universe expanded
Page 10 of 12
B1
Marks
hydrogen gas in stellar cloud / nebula pulled together by gravity
Answer
A1
(2 × 1014 Am atoms remain after) 940 yrs or 2 half-lives
C1
B1
C1
14
– 6 × 10 ) = 2 × 10
14
4 × 1014 (Am atoms remain after 470 yrs or 1 half-life)
(No of Am atoms remaining = 8 × 10
14
gamma and beta will not produce enough ions / ion pairs per cm
B1
4
a
2
Marks
A1
C1
B1
Answer
8.5 # 10-10
0.25
C1
Marks
For examination
from 2020
237
Np
93
(I =) 3.4 × 10–9 A
correct use of f = 4 Hz OR T = 0.25 s i.e. 8.5 × 10–10 × 4 OR
Q = It in any form OR
Answer
Cambridge IGCSE – Mark Scheme
SPECIMEN
© UCLES 2020
12(b)
12(a)
Question
0625/04
0.050 A
Is # Vs
2.0 # 6
OR
Vp
240
Page 11 of 12
A1
C1
A1
200
IpVp = IsVs in any form OR (Ip =)
C1
Marks
For examination
from 2023
Np # Vs
Ns Vs
8000 # 6
in any form OR (Ns =)
OR
=
Vp
Np Vp
240
Answer
Cambridge IGCSE – Mark Scheme
SPECIMEN
© UCLES 2020
0625/04
Page 12 of 12
BLANK PAGE
Cambridge IGCSE – Mark Scheme
SPECIMEN
For examination
from 2020
Cambridge IGCSE™
PHYSICS
0625/41
Paper 4 Extended Theory
May/June 2023
MARK SCHEME
Maximum Mark: 80
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 before 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 Report for
Teachers.
Cambridge International will not enter into discussions about these mark schemes.
Cambridge International is publishing the mark schemes for the May/June 2023 series for most
Cambridge IGCSE, Cambridge International A and AS Level and Cambridge Pre-U components, and some
Cambridge O Level components.
This document consists of 14 printed pages.
© UCLES 2023
[Turn over
0625/41
Cambridge IGCSE – Mark Scheme
PUBLISHED
Generic Marking Principles
May/June 2023
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.
GENERIC MARKING PRINCIPLE 2:
Marks awarded are always whole marks (not half marks, or other fractions).
GENERIC MARKING PRINCIPLE 3:
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.
GENERIC MARKING PRINCIPLE 4:
Rules must be applied consistently, e.g. in situations where candidates have not followed instructions or in the application of generic level
descriptors.
© UCLES 2023
Page 2 of 14
0625/41
Cambridge IGCSE – Mark Scheme
PUBLISHED
May/June 2023
GENERIC MARKING PRINCIPLE 5:
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).
GENERIC MARKING PRINCIPLE 6:
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.
© UCLES 2023
Page 3 of 14
0625/41
Cambridge IGCSE – Mark Scheme
PUBLISHED
May/June 2023
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.
© UCLES 2023
Page 4 of 14
0625/41
6
Cambridge IGCSE – Mark Scheme
PUBLISHED
May/June 2023
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.
© UCLES 2023
Page 5 of 14
0625/41
Cambridge IGCSE – Mark Scheme
PUBLISHED
May/June 2023
Acronyms and shorthand in the mark scheme
Acronym / shorthand
Explanation
A mark
Final answer mark which is awarded for fully correct final answers including the unit.
C mark
Compensatory mark which may be scored when the final answer (A) mark for a question has not been awarded.
B mark
Independent mark which does not depend on any other mark.
M mark
Method mark which must be scored before any subsequent final answer (A) mark can be scored.
Brackets ( )
Words not explicitly needed in an answer, however if a contradictory word / phrase / unit to that in the brackets is seen
the mark is not awarded.
Underlining
The underlined word (or a synonym) must be present for the mark to be scored. If the word is a technical scientific term,
the word must be there.
/ or OR
Alternative answers any one of which gains the credit for that mark.
owtte
Or words to that effect.
ignore
Indicates either an incorrect or irrelevant point which may be disregarded, i.e., not treated as contradictory.
insufficient
An answer not worthy of credit on its own.
CON
An incorrect point which contradicts any correct point and means the mark cannot be scored.
ecf [question part]
Indicates that a candidate using an erroneous value from the stated question part must be given credit here if the
erroneous value is used correctly here.
cao
Correct answer only.
ORA
Or reverse argument.
© UCLES 2023
Page 6 of 14
0625/41
Cambridge IGCSE – Mark Scheme
PUBLISHED
Question
1(a)(i)
Answer
May/June 2023
Marks
(magnitude of velocity =) 0.90 m / s
A2

use of Pythagoras’ theorem e.g. a2 + b2 = c2 OR (speed =)  0.542  0.722

C1
OR
correct vector triangle or rectangle drawn
(direction of velocity =) 53° (to riverbank)
A2
use of trigonometry to find angle e.g. tan = 0.72 / 0.54
C1
OR
(only) angle with horizontal identified on the diagram
1(a)(ii)
1(b)
(distance =) 81 m
A3
v = s / t OR (s =) vt OR (s =) 0.9(0)  90
C1
(time =) 1.5  60 (= 90) OR (time =) 90
C1
friction (of water backwards) OR resistance (on swimmer backwards)
B1
(friction / resistance) balances forward force OR (there is) no resultant force
B1
Question
2(a)(i)
2(a)(ii)
2(b)(i)
© UCLES 2023
Answer
Marks
(speed =) 38 m / s
A2
a = ∆v / ∆t OR (∆v =) a∆t OR (∆v =) 7.2  5.3
C1
(resultant force = ) 1 700 N
A2
F = ma OR (F =) ma OR (F =) 240  7.2
C1
(vector) has direction (as well as magnitude) OR scalar does not have direction
B1
Page 7 of 14
0625/41
Question
Cambridge IGCSE – Mark Scheme
PUBLISHED
Answer
May/June 2023
Marks
2(b)(ii)
(velocity) changes (as direction of motion changes) OR direction (of velocity) changes
B1
2(b)(iii)
any two from:
 because there is an acceleration / change in velocity / change in direction / change in momentum (which needs a
resultant force)
 motorcyclist accelerates / changes momentum (because velocity / direction changes)
 (resultant) force is perpendicular to the motion (of the motorcycle) OR a ∝ F
B2
Question
3(a)
Answer
Marks
heated / hot(ter) / warm(er) air is less dense OR cool(er) air is more dense
B1
heated / hot(ter) / warm(er) air rises (to ceiling displacing cooler air) OR cool(er) air falls (displaced by warm(er) air)
B1
3(b)(i)
speed / velocity (of particles) increases OR (they) move faster
B1
3(b)(ii)
(higher temperature means) particles collide (with rubber) harder / with more force / with greater momentum (change)
B1
(larger volume means) particles collide (with rubber) less frequently
OR
(larger volume means) larger (surface) area (for particle collisions)
B1
effect of larger volume cancels effect of increased temperature / owtte
OR
the effect of larger area cancels the effect of larger force / owtte
OR
P = F / A so the two changes cancel each other / owtte
B1
© UCLES 2023
Page 8 of 14
0625/41
Cambridge IGCSE – Mark Scheme
PUBLISHED
Question
4(a)(i)
4(a)(ii)
Answer
May/June 2023
Marks
c = (∆)E / m∆ OR (∆E =) mc∆
B1
(∆ =) 21.5 – 19 OR (∆ =) 2.5 (°C)
B1
(∆E =) 0.6(0)  4200  2.5 OR (∆E =) 0.6(0)  4200  {21.5 – 19}
B1
(maximum possible efficiency =) 3.1% or 0.031
A4
E = Pt OR (E =) Pt OR (E =) 13  500 OR (E =) 6500
C1
(useful energy output =) 6500 – 6300 OR (useful energy output =) 200
C1
efficiency = useful energy (output) / total energy (input) ( 100%)
OR (efficiency =) useful energy (output) / total energy (input) ( 100%)
OR (efficiency =) {6500 – 6300} / 6500
OR (efficiency =) 200 / 6500 ( 100%)
C1
OR
4(b)
© UCLES 2023
P = E/t OR (P =) E / t OR (P =) 6 300 / 500 OR (P =) 12.6 (W)
(C1)
(useful power output =) total power (output) – wasted power (output)
OR (useful power output =) 13 – {6300 / 500}
OR (useful power output =) 13–12.6
(C1)
efficiency = useful power (output) / total power (input) ( 100%)
OR (efficiency =) useful power (output) / total power (input) ( 100%)
OR (efficiency =) 0.4 / 13 ( 100%)
(C1)
any one from:
 temperature change is an underestimate (due to thermal energy losses)
 (thermal energy is) transferred from the water (to air / beaker / bench)
 energy (other than light) transferred in lamp (filament / glass / internal structure)
 (some) water evaporates
Page 9 of 14
B1
0625/41
Cambridge IGCSE – Mark Scheme
PUBLISHED
Question
Answer
May/June 2023
Marks
5(a)
(light / electromagnetic radiation) of a single frequency
B1
5(b)
angle of incidence / i = 0 OR incident ray along normal
OR all of wavefront enters block at same time
B1
angle of refraction / r = 0 OR no refraction
OR whole wavefront slows down at same time
B1
(c =) sin–1{1 /1.5} (= 42°)
OR
(c =) sin–1 {1 / n} = 41.8°
A2
n = 1 / sin c OR (c =) sin-1 {1 / n} OR (c =) 41.8°
C1
all light is reflected
B1
𝜃 / angle of incidence > c / critical angle
B1
all light is reflected OR reflected ray at 90° to incident ray OR reflected ray is parallel to original ray
B1
5(c)
5(d)(i)
5(d)(ii)
Question
6(a)
6(b)
© UCLES 2023
Answer
Marks
(wavelength =) 0.16 m
A2
v = f OR ( =) v / f OR ( =) 3  108 / 1.9  109
C1
(microwaves) only need short aerials / antennas
B1
(microwaves) penetrate (some) walls
B1
Page 10 of 14
0625/41
Cambridge IGCSE – Mark Scheme
PUBLISHED
Question
6(c)(i)
6(c)(ii)
May/June 2023
Answer
Marks
labelled diagram of digital (signal) with blocks of high (1) and low (0) AND labelled diagram of analogue with continuously
variable signal
B1
digital (signal) consists of two values owtte
B1
analogue (signal) varies over a range (of values) owtte
B1
any two from:
 faster (data) transmission rate OR data can be compressed
 data / signal transmitted over long(er) distances (as signal can be regenerated)
 noise easily removed (from signal / data) OR signal can be regenerated
B2
Question
Answer
Marks
any two from:
 (potential divider) splits / shares / divides the e.m.f. / voltage / potential difference / p.d. (of a power source / in a circuit)
 (e.m.f. is) split between (two) resistors / components (connected in series to power source)
 (potential divider shares e.m.f.) in proportion to the resistances (of the resistors / components)
B2
7(b)(i)
(e.m.f. =) 15 V
B1
7(b)(ii)
(resistance =) 60 
A3
(Rll =) R2R3 / (R2 + R3) OR (Rll =) 40  40 / (40 + 40) OR (Rll =) 1600 / 80
OR 1 / Rll = 1 / R2 + 1 / R3 OR 1 / Rll = 1 / 40 + 1 / 40 OR (Rll =) (1 / 40 + 1 / 40)–1 OR (Rll =) 20 ()
C1
(resistance =) 40 + (candidate’s value for combined resistance of R2 and R3)
C1
7(a)
© UCLES 2023
Page 11 of 14
0625/41
Cambridge IGCSE – Mark Scheme
PUBLISHED
Question
7(c)
Answer
8(b)(i)
8(b)(ii)
© UCLES 2023
Marks
(reading =) 10 V
A2
emf shared in same proportion as resistance
OR e.g. R1 / Rll = V1 / Vll
OR (reading =) 15  40 / 60 OR (reading =) 0.25  40
C1
Question
8(a)
May/June 2023
Answer
Marks
any four from:
 alternating current in (primary coil)
 (current in primary generates) changing magnetic field
 iron core concentrates (magnetic) field OR iron core transfers (magnetic) field (to secondary coil)
 secondary coil is in alternating / changing (magnetic) field OR secondary coil cuts (magnetic) field
 e.m.f. induced (in secondary coil)
B4
(number of turns =) 3000
A2
Np / Ns = Vp / Vs OR (Np =) Ns Vp / Vs OR (Np =) 450  220 000 / 33 000
C1
(current =) 350 A
A3
P = IV OR (I =) P / V OR (I =) 7.7  107 / 220 000
C1
(I =) 3.5  10N
C1
Page 12 of 14
0625/41
Cambridge IGCSE – Mark Scheme
PUBLISHED
Question
9(a)
Answer
May/June 2023
Marks
(number of neutrons =) 7
B1
any one from:
 number of electrons = number of protons
 white dots are protons / there are 5 protons
 grey dots are neutrons
 (number of neutrons) = 12 – 5
B1
(X2 has) one more proton more and one fewer neutron (than X1) OR (X2 has) 6 protons and 6 neutrons
A2
(X2 has) one neutron fewer / one more proton (than X1)
OR (X2 has) 6 protons / 6 neutrons
C1
9(b)(ii)
(X2) has fewer (excess) neutrons (in its nucleus) ORA
B1
9(c)(i)
time (taken)
M1
for number of (radioactive) nuclei / atoms (in a sample of X1) to halve OR for rate of decay to halve
A1
large number of particles produced in short time OR high / large decay rate OR high dose (of radiation) in short time
B1
9(b)(i)
9(c)(ii)
Question
10(a)(i)
© UCLES 2023
Answer
(speed) decreases (from X to Y) and then increases (from Y to X)
Page 13 of 14
Marks
B1
0625/41
Cambridge IGCSE – Mark Scheme
PUBLISHED
Question
Answer
May/June 2023
Marks
10(a)(ii)
any three from:
 gravitational (potential) energy (GPE) transfers to kinetic energy (KE) or vice versa
 KE transfers to GPE from X to Y AND GPE transfers to KE from Y to X
 speed decreases as KE decreases / ORA
 most GPE at Y OR least GPE at X
 total (of GPE + KE) energy is constant
B3
10(b)(i)
–230 (°C)
B1
10(b)(ii)
(white surface) is a poor absorber / good reflector / poor emitter of IR / radiation
OR black / other surface is a good absorber / poor reflector / good emitter of IR / radiation
B1
any one from:
 (the white surface) increases in temperature less when facing the Sun
 (the white surface) decreases in temperature less when facing away (from Sun)
 the black / other surfaces increases in temperature more when facing the Sun
 the black / other surface decreases in temperature more when facing away (from Sun)
 less variation in temperature on white surface (during one whole rotation)
B1
© UCLES 2023
Page 14 of 14
Cambridge IGCSE™
PHYSICS
0625/42
Paper 4 Extended Theory
May/June 2023
MARK SCHEME
Maximum Mark: 80
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 before 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 Report for
Teachers.
Cambridge International will not enter into discussions about these mark schemes.
Cambridge International is publishing the mark schemes for the May/June 2023 series for most
Cambridge IGCSE, Cambridge International A and AS Level and Cambridge Pre-U components, and some
Cambridge O Level components.
This document consists of 12 printed pages.
© UCLES 2023
[Turn over
0625/42
Cambridge IGCSE – Mark Scheme
PUBLISHED
Generic Marking Principles
May/June 2023
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.
GENERIC MARKING PRINCIPLE 2:
Marks awarded are always whole marks (not half marks, or other fractions).
GENERIC MARKING PRINCIPLE 3:
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.
GENERIC MARKING PRINCIPLE 4:
Rules must be applied consistently, e.g. in situations where candidates have not followed instructions or in the application of generic level
descriptors.
© UCLES 2023
Page 2 of 12
0625/42
Cambridge IGCSE – Mark Scheme
PUBLISHED
May/June 2023
GENERIC MARKING PRINCIPLE 5:
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).
GENERIC MARKING PRINCIPLE 6:
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.
© UCLES 2023
Page 3 of 12
0625/42
Cambridge IGCSE – Mark Scheme
PUBLISHED
May/June 2023
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.
© UCLES 2023
Page 4 of 12
0625/42
6
Cambridge IGCSE – Mark Scheme
PUBLISHED
May/June 2023
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.
© UCLES 2023
Page 5 of 12
0625/42
Cambridge IGCSE – Mark Scheme
PUBLISHED
May/June 2023
Acronyms and shorthand in the mark scheme
Acronym / shorthand
Explanation
A mark
Final answer mark which is awarded for fully correct final answers including the unit.
C mark
Compensatory mark which may be scored when the final answer (A) mark for a question has not been awarded.
B mark
Independent mark which does not depend on any other mark.
M mark
Method mark which must be scored before any subsequent final answer (A) mark can be scored.
Brackets ( )
Words not explicitly needed in an answer, however if a contradictory word / phrase / unit to that in the brackets is seen
the mark is not awarded.
Underlining
The underlined word (or a synonym) must be present for the mark to be scored. If the word is a technical scientific term,
the word must be there.
/ or OR
Alternative answers any one of which gains the credit for that mark.
owtte
Or words to that effect.
ignore
Indicates either an incorrect or irrelevant point which may be disregarded, i.e., not treated as contradictory.
insufficient
An answer not worthy of credit on its own.
CON
An incorrect point which contradicts any correct point and means the mark cannot be scored.
ecf [question part]
Indicates that a candidate using an erroneous value from the stated question part must be given credit here if the
erroneous value is used correctly here.
cao
Correct answer only.
ORA
Or reverse argument.
© UCLES 2023
Page 6 of 12
0625/42
Cambridge IGCSE – Mark Scheme
PUBLISHED
Question
1(a)(i)
1(a)(ii)
1(b)(i)
1(b)(ii)
Answer
© UCLES 2023
Marks
no resultant / net force
B1
no resultant/net moment
B1
4.7  107 J or 47 MJ
A2
(∆)Ep = mg(∆)h OR (∆Ep =) mg(∆)h OR (∆Ep =) 3200  9.8  1500
C1
point, labelled 1, on either of the horizontal sections of the graph (to the left of A or to the left of B)
B1
point, labelled 2, on the graph between A and the start of the horizontal section of the graph to the left of B
B1
point, labelled 3, on the graph between the start of the curved section to the right of the origin and the start of the horizontal
section of the graph to the left of A
B1
(initially there is acceleration due to) weight OR gravitational force
OR unbalanced force / resultant force / downward force
B1
(then) air resistance increases as speed or velocity increases
B1
(as air resistance increases) resultant force downwards decreases OR acceleration decreases
B1
constant speed when air resistance = weight / gravitational force
B1
Question
2(a)
May/June 2023
Answer
Marks
26 J
A3
EK = ½mv2 OR (EK =) ½mv2 OR (EK =) ½  0.16  (18)2
C1
(EK =) ½  0.16  (18)2 OR (EK =) ½  0.16  324 OR (EK =) 2.6  10N
C1
Page 7 of 12
0625/42
Cambridge IGCSE – Mark Scheme
PUBLISHED
Question
2(b)
2(c)
Answer
3(b)
A2
Ft = ∆mv OR F = ma OR (F =) (0.16  18) / 0.12
C1
longer time (of impact / contact) AND smaller force (on them)
OR longer time (of impact / contact) AND does not hurt as much
B1
Answer
© UCLES 2023
Marks
(force of gravity / weight of person is spread over a much) greater area
B1
p = F/A OR p ∝ 1/A
B1
(force is same so) pressure is lower (so ice is less likely to crack)
B1
5.8  103 Pa
A4
p (due to water) = gh OR (p =) gh OR (p =) 1000  9.8  0.45 OR (p =) 4410
C1
W = mg OR (W =) mg OR (W =) (690  9.8) OR (W =) 6762 OR (p (due to ice) =) 1352.4
C1
(pressure =) candidate’s calculated pressure due to water + candidate’s calculated pressure due to ice
OR total pressure = [1000  9.8  0.45] + [(690  9.8) / 5.0]
OR total pressure = 4410 + 1352.4
C1
Question
4(a)
Marks
24 N
Question
3(a)
May/June 2023
Answer
Marks
pressure decreases AND particles have smaller velocity / momentum / smaller EK / kinetic energy (when temperature is
lower)
B1
lower rate / frequency of collision of particles
B1
particles collide with smaller force OR smaller impulse change
B1
Page 8 of 12
0625/42
Cambridge IGCSE – Mark Scheme
PUBLISHED
Question
Answer
May/June 2023
Marks
4(b)(i)
–273 (°C)
B1
4(b)(ii)
(temperature at which) particles have least EK / kinetic energy
B1
lowest possible temperature
B1
200 cm3
A3
pV = constant OR 9.0  104  350 = 1.6  105  V2
C1
V2 = [9.0  104  350] / 1.6  105 OR V2 = 2.0  10N OR 1.97  10N
C1
4(c)
Question
5(a)(i)
5(a)(ii)
5(a)(iii)
5(b)
© UCLES 2023
Answer
Marks
 = m / V OR m =  V
B1
(m =) 1.2  4.5  6.1  2.4 (= 79 kg) OR (m =) 79.056 (kg)
B1
290 s
A4
c = (∆)E / m∆ OR (∆E =) mc∆ OR (∆E =) 79  1000  4(.0) OR (∆E =) 316 000 OR (∆ =) 4(.0)
C1
P = (∆)E / t OR (∆E =) Pt OR (∆E =) 1100  t
C1
(t =) mc∆ / P OR (t =) 79  1000  4(.0) / 1100 OR (t =) 316 000 / 1100
C1
any one from:
 (thermal) energy is transferred to furniture / walls / objects (in the room)
 (thermal) energy is transferred through windows / doors / floor / ceiling / from the room
B1
conduction AND convection
B1
Page 9 of 12
0625/42
Cambridge IGCSE – Mark Scheme
PUBLISHED
Question
6(a)
6(b)
Answer
May/June 2023
Marks
P-waves: longitudinal
B1
S-waves: transverse
B1
1600 m OR 1.6 km
A3
v = f OR ( =) v / f
C1
( =) [7.2  1000] / 4.5 OR ( =) 1.6  10N OR ( =) 7.2 / 4.5
C1
Question
Answer
Marks
7(a)
normal drawn in correct position and at right angles to the surface
B1
7(b)
22°
A3
i = 34(°)
C1
n = sin i / sin r OR (r =) sin–1 {sin i / n} OR sin r = sin 34 / 1.47 OR sin r = 0.38
C1
7(c)
3.0  108 m / s
B1
7(d)
2.04  108 m / s
A2
n = speed of light in air / speed of light in oil
OR (speed of light in oil =) speed of light in air / n
OR (speed of light in oil =) 3.0  108 / 1.47
C1
Question
Answer
Marks
8(a)(i)
region in which a (magnetic) pole experiences a force
B1
8(a)(ii)
in the direction of the force on the N pole
B1
© UCLES 2023
Page 10 of 12
0625/42
Cambridge IGCSE – Mark Scheme
PUBLISHED
Question
8(b)
Answer
May/June 2023
Marks
4 radial lines outside sphere, touching the sphere and equally spaced all around sphere
B1
direction of arrows towards the sphere
B1
8(c)(i)
2.0 V
A1
8(c)(ii)
(ratio of p.d. across R2 : R3 =) 1 : 2
B1
8(c)(iii)1.
current is zero in R1 AND diode is in wrong direction (to allow current) owtte
B1
8(c)(iii)2.
(ratio of p.d. across R2 : R3 =) 1 : 1
B1
Question
Answer
Marks
 – no. of neutrons 2
B1
 – no. of protons 0 and charge –1.6  10–19
B1
 – no. of neutrons 0 and charge 0 and (very) thick concrete / thick lead
B1
9(b)
(the nucleus has) one less neutron and one more proton
B1
9(c)
95 (counts / min)
A4
initial count rate due to source = 550 – 30 (counts / min) OR 520 seen
C1
(75 min =) 3 half-lives OR (count rate =) 1 / 8 (of initial count rate)
C1
final count rate due to source = (520 / 8 =) 65
C1
any two from:
 limit time of exposure
 store sources in lead boxes
 keep distance from sources
 avoid contact OR use tongs OR wear gloves
B2
9(a)
9(d)
© UCLES 2023
Page 11 of 12
0625/42
Cambridge IGCSE – Mark Scheme
PUBLISHED
Question
10(a)
Answer
May/June 2023
Marks
v = 2r / T
B1
r = (average) radius of the orbit AND T = (orbital) period
B1
10(b)
rays from Sun strike the country at different angles through the year
OR
rays from Sun strike the country for different number of hours per day through the year
B1
10(c)
(first space:) red supergiant
B1
(second space:) nebula
B1
(3rd and 4th spaces:) neutron star
B1
black hole
B1
1.6  109 (light-years)
A2
H0 = v / d OR (d =) v / H0 OR (d =) [33 000  103] / [ 2.2  10–18  9.5  1015]
C1
10(d)
© UCLES 2023
Page 12 of 12
Cambridge IGCSE™
PHYSICS
0625/43
Paper 4 Extended Theory
May/June 2023
MARK SCHEME
Maximum Mark: 80
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 before 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 Report for
Teachers.
Cambridge International will not enter into discussions about these mark schemes.
Cambridge International is publishing the mark schemes for the May/June 2023 series for most
Cambridge IGCSE, Cambridge International A and AS Level and Cambridge Pre-U components, and some
Cambridge O Level components.
This document consists of 14 printed pages.
© UCLES 2023
[Turn over
0625/43
Cambridge IGCSE – Mark Scheme
PUBLISHED
Generic Marking Principles
May/June 2023
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.
GENERIC MARKING PRINCIPLE 2:
Marks awarded are always whole marks (not half marks, or other fractions).
GENERIC MARKING PRINCIPLE 3:
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.
GENERIC MARKING PRINCIPLE 4:
Rules must be applied consistently, e.g. in situations where candidates have not followed instructions or in the application of generic level
descriptors.
© UCLES 2023
Page 2 of 14
0625/43
Cambridge IGCSE – Mark Scheme
PUBLISHED
May/June 2023
GENERIC MARKING PRINCIPLE 5:
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).
GENERIC MARKING PRINCIPLE 6:
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.
© UCLES 2023
Page 3 of 14
0625/43
6
Cambridge IGCSE – Mark Scheme
PUBLISHED
May/June 2023
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.
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Acronyms and shorthand in the mark scheme
Acronym / shorthand
Explanation
A mark
Final answer mark which is awarded for fully correct final answers including the unit.
C mark
Compensatory mark which may be scored when the final answer (A) mark for a question has not been awarded.
B mark
Independent mark which does not depend on any other mark.
M mark
Method mark which must be scored before any subsequent final answer (A) mark can be scored.
Brackets ( )
Words not explicitly needed in an answer, however if a contradictory word / phrase / unit to that in the brackets is seen
the mark is not awarded.
Underlining
The underlined word (or a synonym) must be present for the mark to be scored. If the word is a technical scientific term,
the word must be there.
/ or OR
Alternative answers any one of which gains the credit for that mark.
owtte
Or words to that effect.
ignore
Indicates either an incorrect or irrelevant point which may be disregarded, i.e., not treated as contradictory.
insufficient
An answer not worthy of credit on its own.
CON
An incorrect point which contradicts any correct point and means the mark cannot be scored.
ecf [question part]
Indicates that a candidate using an erroneous value from the stated question part must be given credit here if the
erroneous value is used correctly here.
cao
Correct answer only.
ORA
Or reverse argument.
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Question
Answer
May/June 2023
Marks
1(a)
1200 N AND
g = W / m OR (W =) mg OR (W =) 120  9.8
B1
1(b)
F = ma OR (a =) F / m
B1
(a =) 54 / 120
B1
(v =) 3.6 m / s
A2
a = (∆)v / t OR (∆v =) at OR (∆v =) 0.45  8(.0)
C1
(d =) 14 m
A2
 3.6 
average speed = (total) distance travelled / (total) time taken OR 1.8  8 OR 
8
 2 
C1
1(c)
1(d)
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Question
Answer
May/June 2023
Marks
2(a)(i)
(pressure is) force per unit area
B1
2(a)(ii)
(variation with depth) increases (as depth increases)
B1
(variation with density) increases (as density increases)
B1
any two from:
 geothermal
 nuclear
 tidal
B2
(statement) non-renewable / not renewable / no
B1
(explanation) (nuclear) fuel is used up
B1
(statement) renewable / yes
B1
(explanation) waves will always continue OR produced by wind which will always continue OR nothing used up
B1
2(b)
2(c)(i)
2(c)(ii)
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Question
3(a)(i)
Answer
May/June 2023
Marks
(greatest) gas
B1
(least) solid
B1
3(a)(ii)
any three from:
 (solids) particles vibrate
 (gases) particles move freely
 (solids) particles in fixed / close positions
 (gases) particles randomly arranged (in container) / wide separation
 (gas) particles move quickly
B3
3(b)(i)
(specific heat capacity is the) energy required to raise 1 kg / unit mass by 1 °C / 1 K / 1 kelvin / unit temperature
A2
energy required per unit mass / 1 kg
OR energy required per unit temperature / 1 °C increase / 1 K increase / 1 kelvin increase
C1
time
B1
mass
B1
initial temperature AND final temperature
B1
3(b)(ii)
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Question
4(a)(i)
May/June 2023
Answer
Marks
two correct rays extended back (towards the intersection)
M1
extended rays intersect
A1
image drawn from intersection to principal axis AND base of image lies in correct range
B1
4(a)(ii)
circles around:
 enlarged
 virtual
 upright
B3
4(b)(i)
long-sightedness / long sight / far-sighted
B1
4(b)(ii)
converging lens reduces focal length of eye OR converging lens brings focal point forward OR without lens, rays converge
behind back of eye
B1
(so that) rays converge / focus on back of eye / retina
B1
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Question
Answer
May/June 2023
Marks
5(a)(i)
infrared
B1
5(a)(ii)
glass is transparent to visible light and (some) IR
B1
(visible light and some IR) can carry high rates of data / information
B1
(n =) 1.4
A2
(n =) 1 / sin c OR (n =) 1 / sin c OR (n =) 1 / sin 45
C1
diagram shows that total internal reflection is taking place inside optical fibre
B1
one or more correct reflections with i > 45°
B1
5(b)(i)
5(b)(ii)
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Question
6(a)
Answer
6(c)
© UCLES 2023
C1
P
2500
OR I 2 
R
26
I2 = 2500 / 26 OR (I =) √(P / R) OR
6(b)
Marks
A3
(I =) 9.8 A
P = I 2R OR I 2 
May/June 2023
C1
2500
26
(R =) 53 
A3
R ∝ l OR 1.8 / 1.2 OR 1.5 seen as multiplier
C1
R ∝ 1 / A OR 7.9 ( 10–7) / 5.8 ( 10–7) OR 1.36(2) seen as multiplier
C1
(cost =) $36
A2
E = Pt AND (cost =) E  0.3(0) OR (cost =) 25  10N  2  24  0.3(0)
OR 3.6  10N dollars
C1
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Question
7(a)
7(b)
Answer
May/June 2023
Marks
(Ip =) 0.14 A
A3
Vp Ip = Vs Is OR (Ip =) Vs Is / Vp OR (Ip =) 12  2.5 / 220
C1
(Ip =) 12  2.5 / 220
C1
(turns ratio =) 18 (: 1)
A2
Np / Ns = Vp / Vs OR (Np / Ns =) Vp / Vs OR (turns ratio =) 220 / 12
C1
Question
Answer
Marks
8(a)(i)
(neutron) becomes proton and electron OR (neutron) becomes proton and β particle
B1
8(a)(ii)
charge on neutron = 0 OR total charge on products = 0
B1
charge on proton = +1 AND charge on electron = –1
B1
8(b)
( 212
86 Rn )
208
84 Po
A3
+ 42 
any two from:
 proton numbers balance
 nucleon numbers balance
4
4

2  OR 2He seen
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C2
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Question
9(a)
Answer
May/June 2023
Marks
both positions correctly marked S1 and J1 on the diagram
A3
Saturn moved 360  5 / 30 (= 60°) OR S1 in correct position
C1
Jupiter moved 360  5 / 12 (= 150°) OR J1 in correct position
C1
9(b)(i)
S2 at 240° AND J2 at (600° – 360° =) 240°
B1
9(b)(ii)
(Saturn and Jupiter) are aligned / Jupiter exactly in front of Saturn / there is a conjunction owtte
B1
9(c)(i)
(Jupiter) gaseous AND large
AND
(Earth) rocky AND small
B1
9(c)(ii)
any three from:
B3
(density)
 Jupiter has a low density because it is composed of gas / Earth has a high density because it is a solid
(gravitational field strength)
 Jupiter (has a large GFS so it) has a large mass / Earth (has a small GFS so it) has a small mass
 Jupiter’s mass is larger than the Earth’s mass because the volume of Jupiter is larger even though the density of
Jupiter is smaller
9(d)
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(mass =) 1.8  1027 kg
A3
ρ = m / V OR (m =) ρV OR (m =) 1300  1.4  1015  109
C1
(m =) 1300  1.4  1015  109 (kg) OR 1.8(2)  10N
C1
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Question
10(a)
Answer
May/June 2023
Marks
v = s / t OR (s =) vt
B1
(c =) 3  108 (m / s)
B1
(1 year =) 365  24  3600 (s) OR 3.2  107 (s) OR 32  106 OR 8760  3600
B1
(s =) candidate’s speed of light  candidate’s time (m)
B1
10(b)(i)
change of wavelength (of galaxy’s starlight) OR redshift
B1
10(b)(ii)
H0 = v / d
B1
10(b)(iii)
brightness of a supernova
B1
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