Please check the examination details below before entering your candidate information
Candidate surname Other names
Centre Number Candidate Number
Pearson Edexcel International Advanced Level
Wednesday 4 June 2025
Morning (Time: 1 hour 45 minutes) Paper
reference WPH15/01
Physics
International Advanced Level
UNIT 5: Thermodynamics, Radiation, Oscillations
and Cosmology
You must have: Total Marks
Scientific calculator, ruler
Instructions:
•• Use black ink or ball‑point pen.
If pencil is used for diagrams/sketches/graphs it must be dark (HB or B).
• Fill in the boxes at the top of this page with your name,
centre number and candidate number.
•• Answer all questions.
Answer the questions in the spaces provided
– there may be more space than you need.
• Show all your working out in calculations and include units where appropriate.
Information:
• The total mark for this paper is 90.
• – usemarks
The for each question are shown in brackets
this as a guide as to how much time to spend on each question.
• to structure
In the question marked with an asterisk (*), marks will be awarded for your ability
your answer logically, showing how the points that you make are
related or follow on from each other where appropriate.
• The list of data, formulae and relationships is printed at the end of this booklet.
Advice:
• Read each question carefully before you start to answer it.
•• Checkanswer
Try to every question.
your answers if you have time at the end.
Turn over
P78758A
©2025 Pearson Education Ltd.
Y:1/1/1/1/
*P78758A0132*
, SECTION A
Answer ALL questions.
DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
For questions 1–10, in Section A, select one answer from A to D and put a cross in the box .
If you change your mind, put a line through the box and then mark your new answer with a
cross .
1: Which of the following statements applies to both electric fields and gravitational fields?
A Each field causes a force on all particles.
B Each field can cause an attractive or repulsive force.
C Field strength is proportional to the square of the distance from a point source.
D F
ield strength is inversely proportional to the square of the distance from a
point source.
(Total for Question 1 = 1 mark)
2: A mass is driven into oscillation, and resonance takes place.
Which of the following statements is not correct?
A The amplitude of oscillation of the mass is a maximum.
B The frequency of oscillation of the mass is a maximum.
C The mass is driven at its natural frequency.
D The transfer of energy to the mass is a maximum.
(Total for Question 2 = 1 mark)
3: Energy is released when the fusion of low mass nuclei takes place.
Energy is also released when the fission of high mass nuclei takes place.
Which row of the table shows the change in binding energy per nucleon (B.E. / nucleon)
for fusion and fission?
Nuclear fusion Nuclear fission
A B.E. / nucleon decreases B.E. / nucleon decreases
B B.E. / nucleon decreases B.E. / nucleon increases
C B.E. / nucleon increases B.E. / nucleon decreases
D B.E. / nucleon increases B.E. / nucleon increases
(Total for Question 3 = 1 mark)
2
*P78758A0232*
, 4: A megaparsec, Mpc, is a unit of distance used by astronomers.
1 Mpc = 3.1 × 1022 m
DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
Recent estimates of the Hubble constant give a value of 74 km s–1 Mpc–1.
Which of the following gives the age of the universe in seconds?
74
A
3.1 × 1022
B 74 × 103
3.1 × 1022
C 3.1 × 1022
74
D 3.1 × 1022
74 × 103
(Total for Question 4 = 1 mark)
5: On Earth, hydrogen is observed to emit a spectral line with a wavelength of 410 nm.
The same spectral line is observed in the radiation received from a galaxy that is
moving away from the Earth at a speed of 0.1 c.
Which of the following is the wavelength of the spectral line in the radiation received
from the galaxy?
A 451 nm
B 430 nm
C 410 nm
D 369 nm
(Total for Question 5 = 1 mark)
3
*P78758A0332* Turn over
, 6: In a laboratory, the background count rate is 22 counts per minute.
A detector is placed 25 cm from a gamma source. The count rate recorded by the
DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
detector is 54 counts per minute.
The detector is then placed 50 cm from the source.
Which of the following is the expected number of counts per minute?
54 22
A
22
2
54 22
B
22
4
54 22
C
22
2
D
54 22 22
4
(Total for Question 6 = 1 mark)
7: A student used a detector to determine the intensity of radiation from a source of gamma
radiation. After correcting for background, the intensity of radiation recorded by the
detector was I0.
A lead sheet of thickness 2.5 cm was placed between the source and the detector.
The corrected intensity of radiation recorded by the detector was now 0.50 I0.
The original lead sheet was replaced by a new lead sheet of thickness 7.5 cm.
Which of the following was the corrected intensity of gamma radiation recorded by
the detector?
A 0.33 I0
B 0.25 I0
C 0.13 I0
D 0.06 I0
(Total for Question 7 = 1 mark)
4
*P78758A0432*
Candidate surname Other names
Centre Number Candidate Number
Pearson Edexcel International Advanced Level
Wednesday 4 June 2025
Morning (Time: 1 hour 45 minutes) Paper
reference WPH15/01
Physics
International Advanced Level
UNIT 5: Thermodynamics, Radiation, Oscillations
and Cosmology
You must have: Total Marks
Scientific calculator, ruler
Instructions:
•• Use black ink or ball‑point pen.
If pencil is used for diagrams/sketches/graphs it must be dark (HB or B).
• Fill in the boxes at the top of this page with your name,
centre number and candidate number.
•• Answer all questions.
Answer the questions in the spaces provided
– there may be more space than you need.
• Show all your working out in calculations and include units where appropriate.
Information:
• The total mark for this paper is 90.
• – usemarks
The for each question are shown in brackets
this as a guide as to how much time to spend on each question.
• to structure
In the question marked with an asterisk (*), marks will be awarded for your ability
your answer logically, showing how the points that you make are
related or follow on from each other where appropriate.
• The list of data, formulae and relationships is printed at the end of this booklet.
Advice:
• Read each question carefully before you start to answer it.
•• Checkanswer
Try to every question.
your answers if you have time at the end.
Turn over
P78758A
©2025 Pearson Education Ltd.
Y:1/1/1/1/
*P78758A0132*
, SECTION A
Answer ALL questions.
DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
For questions 1–10, in Section A, select one answer from A to D and put a cross in the box .
If you change your mind, put a line through the box and then mark your new answer with a
cross .
1: Which of the following statements applies to both electric fields and gravitational fields?
A Each field causes a force on all particles.
B Each field can cause an attractive or repulsive force.
C Field strength is proportional to the square of the distance from a point source.
D F
ield strength is inversely proportional to the square of the distance from a
point source.
(Total for Question 1 = 1 mark)
2: A mass is driven into oscillation, and resonance takes place.
Which of the following statements is not correct?
A The amplitude of oscillation of the mass is a maximum.
B The frequency of oscillation of the mass is a maximum.
C The mass is driven at its natural frequency.
D The transfer of energy to the mass is a maximum.
(Total for Question 2 = 1 mark)
3: Energy is released when the fusion of low mass nuclei takes place.
Energy is also released when the fission of high mass nuclei takes place.
Which row of the table shows the change in binding energy per nucleon (B.E. / nucleon)
for fusion and fission?
Nuclear fusion Nuclear fission
A B.E. / nucleon decreases B.E. / nucleon decreases
B B.E. / nucleon decreases B.E. / nucleon increases
C B.E. / nucleon increases B.E. / nucleon decreases
D B.E. / nucleon increases B.E. / nucleon increases
(Total for Question 3 = 1 mark)
2
*P78758A0232*
, 4: A megaparsec, Mpc, is a unit of distance used by astronomers.
1 Mpc = 3.1 × 1022 m
DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
Recent estimates of the Hubble constant give a value of 74 km s–1 Mpc–1.
Which of the following gives the age of the universe in seconds?
74
A
3.1 × 1022
B 74 × 103
3.1 × 1022
C 3.1 × 1022
74
D 3.1 × 1022
74 × 103
(Total for Question 4 = 1 mark)
5: On Earth, hydrogen is observed to emit a spectral line with a wavelength of 410 nm.
The same spectral line is observed in the radiation received from a galaxy that is
moving away from the Earth at a speed of 0.1 c.
Which of the following is the wavelength of the spectral line in the radiation received
from the galaxy?
A 451 nm
B 430 nm
C 410 nm
D 369 nm
(Total for Question 5 = 1 mark)
3
*P78758A0332* Turn over
, 6: In a laboratory, the background count rate is 22 counts per minute.
A detector is placed 25 cm from a gamma source. The count rate recorded by the
DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
detector is 54 counts per minute.
The detector is then placed 50 cm from the source.
Which of the following is the expected number of counts per minute?
54 22
A
22
2
54 22
B
22
4
54 22
C
22
2
D
54 22 22
4
(Total for Question 6 = 1 mark)
7: A student used a detector to determine the intensity of radiation from a source of gamma
radiation. After correcting for background, the intensity of radiation recorded by the
detector was I0.
A lead sheet of thickness 2.5 cm was placed between the source and the detector.
The corrected intensity of radiation recorded by the detector was now 0.50 I0.
The original lead sheet was replaced by a new lead sheet of thickness 7.5 cm.
Which of the following was the corrected intensity of gamma radiation recorded by
the detector?
A 0.33 I0
B 0.25 I0
C 0.13 I0
D 0.06 I0
(Total for Question 7 = 1 mark)
4
*P78758A0432*
