AQA GCSE Physics Physics Paper 2 (Foundation), November 2020: Question 9
13 marks · Standard Demand difficulty · Short Answer
Describe the life cycle of massive stars, calculate light travel time from the Sun, and recall stellar physics concepts.
Practise this questionQuestion
Question text
09.1 Complete the sentences.
[2 marks]
The Sun is a stable star. This is because the forces pulling inwards caused by
are in equilibrium with the forces pushing outwards caused
by the energy released by nuclear .
09.2 Write down the equation that links distance travelled (s), speed (v) and time (t).
[1 mark]
09.3 The mean distance between the Sun and the Earth is 1.5 × 1011 m.
Light travels at a speed of 3.0 × 108 m/s.
Calculate the time taken for light from the Sun to reach the Earth.
[3 marks]
Time = s
09.4 Some stars are much more massive than the Sun.
Describe the life cycle of stars much more massive than the Sun, including the
formation of new elements.
[6 marks]
09.5 Stars emit radiation with a range of wavelengths.
Which property of a star does the range of wavelengths depend on?
[1 mark]
Tick ( ) one box.
Density
Mass
Temperature
Volume
Mark scheme
Show the mark scheme
Question 9
AO /
Question Answers Extra information Mark
Spec. Ref.
09.1 (force of) gravity do not allow weight 1 AO1
4.8.1.1
fusion 1
09.2 distance = speed × time allow a correct re-arrangement 1 AO1
4.5.6.1.2
or
s = vt do not allow d = st
09.3 1.5 × 1011 = 3.0 × 108 × t 1 AO2
4.5.6.1.2
1.5 × 1011 1
t = 8
3.0 × 10
t = 500 (s) 1
Level 3: Scientifically relevant facts, events or processes are AO1
09.4 5–6
identified and given in detail to form an accurate account. 4.8.1.2 17
Level 2: Scientifically relevant facts, events or processes are
identified and their relevance is clear. The account is not fully 3–4
accurate.
Level 1: Facts, events or processes are identified and simply
1–2
stated but their relevance is not clear.
No relevant content 0
Indicative content:
• fusion (processes in stars) produce new elements
• cloud of gas / hydrogen and dust OR nebula
• pulled together by gravity
• causing increasing temperature (to start the fusion process)
• (to become a) protostar
• hydrogen nuclei fuse to form helium nuclei
• and the star becomes main sequence
• hydrogen begins to run out
• helium nuclei fuse to make heavier elements
• up to iron
• the star expands (to become a)
• red super giant
• (the star collapses rapidly) and explodes
• called a supernova
• creating elements heavier than iron
• and distributing them throughout the universe
• leaving behind a neutron star
• or a black hole.
09.5 Temperature 1 AO1
4.6.3.2
Total 13
How to answer it
Forces, Waves, and the Life Cycle of Stars
This question assesses your knowledge of stellar physics (stability of stars, life cycle of massive stars, and black-body radiation), basic mechanics equations, and standard calculation techniques involving standard form numbers.
Part 09.1: Star Stability
Complete the sentences about a stable star. (2 marks)
✅ Correct Answer
- First blank: (force of) gravity
- Second blank: fusion
💡 Key Knowledge
A stable star (like our Sun) is in equilibrium. The inward gravitational force pulling the matter together is perfectly balanced by the outward radiation pressure generated by nuclear fusion in the core.
❌ Common Errors
Writing "weight" instead of gravity will lose the mark—weight is a force acting on an object due to gravity, but here it is the gravitational field/force of the star's mass acting on itself.
Part 09.2: Speed, Distance, and Time Equation
Write down the equation linking distance travelled, speed, and time. (1 mark)
✅ Correct Answer
distance = speed × time OR s = v × t
🧠 Exam Technique
Memorise standard physics formulas word-for-word or using standard letter symbols. Do not alter standard notations (e.g., examiners do not accept d = st here).
Part 09.3: Light Travel Time Calculation
Calculate the time taken for light from the Sun to reach Earth. (3 marks)
📐 Step-by-Step Calculation
- State rearranged formula: t = distance / speed
- Substitute values: t = (1.5 × 10¹¹) / (3.0 × 10⁸)
- Calculate final answer: t = 500 s
❌ Common Calculation Traps
Entering numbers incorrectly into standard form calculators can cause syntax errors. Always put brackets around numerator and denominator values if entering long strings, or use the EXP/10^x button correctly!
Part 09.4: Life Cycle of Massive Stars
Describe the life cycle of stars much more massive than the Sun, including the formation of new elements. (6 marks)
💡 Key Knowledge (The 6-Stage Narrative)
- Nebula: Dust and hydrogen gas pulled together by gravity.
- Protostar: Temperature increases as it gets denser, starting nuclear fusion.
- Main Sequence: Hydrogen nuclei fuse into helium nuclei, maintaining a stable star.
- Red Super Giant: Hydrogen runs out; heavier elements are fused up to iron.
- Supernova: The star expands, collapses rapidly, and explodes.
- Remnants: Distributes elements through the universe, leaving a neutron star or black hole.
🧠 Exam Technique (Level of Response)
This is a 6-mark extended writing question marked using levels (Level 1: 1–2 marks, Level 2: 3–4 marks, Level 3: 5–6 marks). To hit Level 3, you must write a logically sequenced chronological account that explicitly links element creation to specific stages (fusion up to iron in red super giants, elements heavier than iron in supernovae).
Part 09.5: Radiation Wavelengths
Which property of a star does the range of wavelengths depend on? (1 mark)
✅ Correct Answer
Tick: Temperature
💡 Key Knowledge
The intensity and peak wavelength of radiation emitted by a hot body (like a star) depend entirely on its surface temperature. Hotter stars emit a higher proportion of shorter wavelengths (bluer light), while cooler stars emit longer wavelengths (redder light).
Topics
Physics · P5: Forces · P6: Waves · P8: Space Physics (physics only)
Question and mark scheme from the AQA GCSE Physics examination, Physics Paper 2 (Foundation), November 2020. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.