AQA GCSE Physics Physics Paper 2 (Higher), June 2022: Question 2
16 marks · Standard Demand difficulty · Extended Answer
Investigate the refraction and reflection of light including describing a practical method, plotting graph data, completing a ray diagram, and evaluating experimental setups.
Practise this questionQuestion
Question text
02 A student used a ray box to shine a ray of light through air into a glass block.
The student investigated how the angle of refraction varied with the angle of
incidence.
Table 1 shows the results.
Table 1
Angle of incidence in degrees Angle of refraction in degrees
10 5
20 10
30 14
40 19
50 23
60 26
70 28
80 29
02.1 Describe a method the student could have used to obtain the results in Table 1.
Your answer may include a labelled diagram.
[6 marks]
02.2 Figure 2 is an incomplete graph of the results.
Figure 2
Complete Figure 2 using data from Table 1.
• Label the axes.
• Plot the remaining data.
• Draw a line of best fit.
[4 marks]
02.3 Complete the ray diagram in Figure 3 to show the reflection of light from the surface
of a plane mirror.
You should:
*07* • draw the normal line
• draw the reflected ray.
[2 marks]
Figure 3
02.4 Two students investigated the reflection of light by a plane mirror.
Figure 4 shows the different equipment the students used.
Figure 4
Explain two ways that Method A is better than Method B.
[4 marks]
*08* 2
Mark scheme
Show the mark scheme
Question 2
AO /
Question Answers Mark
Spec. Ref.
02.1 Level 3: The method would lead to the production of a valid 5‒6 AO1
outcome. All key steps are identified and logically 4.6.1.3
sequenced.
Level 2: The method would not necessarily lead to a valid 3–4
outcome. Most steps are identified, but the method is not
fully logically sequenced.
Level 1: The method would not lead to a valid outcome. 1–2
Some relevant steps are identified, but links are not made
clear.
No relevant content 0
Indicative content
Some indicative content could be indicated within a labelled
diagram
• place a glass block on a piece of paper
• draw around the glass block
• use the ray box to shine a ray of light through the glass
block
• mark the ray of light entering the glass block
• mark the ray of light emerging from the glass block
• join the points to show the path of the complete ray through
the block
• and draw a normal line at 90 degrees to the surface
• use a protractor to measure the angle of incidence
• use a protractor to measure the angle of refraction
• use a ray box to shine a ray of light at a range of different
angles (of incidence)
• increase the angle of incidence in 10 degree intervals
• from an angle of incidence of 10 degrees to an angle of
incidence of 80 degrees
Methods involving mirrors and reflection score zero
AO /
Question Answers Extra information Mark
Spec. Ref.
02.2 angle of incidence in degrees / ° 1 AO2
on x-axis and angle of refraction 4.6.1.3
in degrees / ° on y-axis
10 all points plotted correctly allow 1 mark if 3 or 4 points 2
plotted correctly
allow tolerance of half a small
square
curved line of best fit allow line of best fit from their 1
incorrectly plotted points
AO /
Spec. Ref.
02.3 normal drawn at 90° at the point 1 AO2
where the incident ray strikes 4.6.1.3
the mirror
straight line drawn with a ruler ignore any arrows 1
and angle of incidence = angle
of reflection
AO /
Spec. Ref.
02.4 (the protractor drawn on the allow do not have to mark the 1 AO3
paper means you) do not have position of the rays of light 4.6.1.3
to move the mirror (to measure
the angles) allow protractor does not need
to be repositioned
(so) more likely to record the allow reducing random error 1
correct angle of incidence and / allow more accurate
or reflection
ray in method A does not allow ray in method A is 1
diverge thin(ner)
(making it) easier to judge the allow more accurate if not 1
centre (position) of the ray already awarded
allow converse answers in terms
of method B being worse than
method A 11
Total Question 2 16
How to answer it
Investigating Refraction & Reflection of Light
📋 What this question tests
This question evaluates understanding of AQA Required Practical 9: Light (refraction and reflection), focusing on:
- Experimental Design (AO1): Writing a sequenced, repeatable method to measure angles of incidence and refraction in a transparent glass block.
- Data Presentation & Graphing (AO2): Adding axis labels with correct units, plotting points accurately (±0.5 small square), and drawing a smooth curved line of best fit.
- Ray Diagram Construction (AO2): Drawing the normal at 90° to a mirror surface and constructing a reflected ray satisfying the Law of Reflection (i = r).
- Evaluating Apparatus (AO3): Comparing experimental set-ups (lasers vs ray boxes, printed scales vs handheld protractors) in terms of beam divergence and reducing measurement errors.
Method: Investigating Angle of Refraction vs Angle of Incidence
Required Practical: Ray box and glass block
✅ Model 6-Mark Method
- Place a rectangular glass block flat on a sheet of plain white paper and draw closely around its boundary with a pencil.
- Remove the block and draw a normal line at 90° to one of the longer sides using a protractor and ruler.
- Use the protractor to mark an incident angle of 10° to the normal.
- Replace the glass block precisely inside the pencil outline.
- Use a ray box with a single slit to shine a narrow ray of light along the 10° line into the block at the normal point.
- Mark the path of the incident and emerging light rays by making small crosses (or dots) along the centre of the rays.
- Turn off the ray box, remove the glass block, and join the entry and exit points with a straight line using a ruler to show the refracted ray inside the block.
- Use a protractor to measure the angle of refraction between the refracted ray and the normal line inside the block outline.
- Repeat this procedure for a range of incident angles from 20° up to 80° in 10° intervals, recording all results in a table.
🧠 Level Descriptors & Examiner Strategy
- Level 3 (5–6 marks): The method leads to a valid outcome. All key steps are explicitly named and logically ordered.
- Level 2 (3–4 marks): Most steps identified, but some omissions (e.g. forgets to mention measuring the angle with a protractor or repeating across the full range).
- Level 1 (1–2 marks): Fragmented steps without clear sequencing.
- Examiner Warning: The mark scheme explicitly states: "Methods involving mirrors and reflection score zero." Ensure you describe refraction through the block, not reflection from a surface!
💡 Key Experimental Vocabulary
- Normal Line: An imaginary line perpendicular (at 90°) to the boundary surface at the exact point of ray entry.
- Angle of Incidence (i): Measured strictly between the incident ray and the normal (NOT the surface).
- Angle of Refraction (r): Measured strictly between the refracted ray inside the block and the normal.
❌ Common Errors to Avoid
- Measuring angles between the ray and the block surface instead of the normal.
- Forgetting to state that the block must be removed before drawing the line connecting the entry point to the exit point.
- Failing to specify the range and interval (e.g. 10° to 80° in 10° steps), even though Table 1 provided these exact numbers.
Completing the Graph of Results
Axis labels, point plotting, and line of best fit
✅ Mark Breakdown (4 Marks Total)
- Mark 1 (Axes): Both axes fully labelled with quantity and unit:
x-axis: Angle of incidence in degrees / °
y-axis: Angle of refraction in degrees / ° - Marks 2 & 3 (Plotting): All five remaining points plotted correctly within ± half a small square tolerance:
• (40, 19) • (50, 23) • (60, 26) • (70, 28) • (80, 29)
(2 marks for all 5 correct; 1 mark if 3 or 4 points correct). - Mark 4 (Line of Best Fit): A single, smooth, continuous curved line drawn through the points starting from the origin (0,0).
❌ Graph Plotting Traps
- Drawing a straight line: As i increases, the rate of increase of r decreases. The graph is distinctly a curve that levels off. Forcing a straight line loses the line mark!
- "Dot-to-dot" lines: Never join individual data points with straight ruler segments.
- Missing units: Writing just "Angle of incidence" without "in degrees" or " / °" loses the axis mark.
- Heavy or "feathery" lines: Use a sharp pencil. A line thicker than half a grid square will be penalised.
Completing a Reflection Ray Diagram
Law of Reflection construction
- The Normal (1 mark): Use a ruler and protractor to draw a straight line (dashed or solid) at exactly 90° to the mirror surface at the exact point where the incident ray hits the mirror.
- The Reflected Ray (1 mark): Measure the angle between the incident ray and the normal (angle of incidence). Draw a sharp straight line extending away from that contact point such that the angle of reflection equals the angle of incidence (i = r).
💡 The Law of Reflection
For any planar reflective surface:
Angle of incidence (i) = Angle of reflection (r)
Note: The mark scheme specifies that arrowheads on the reflected ray are not strictly required for this mark ("ignore any arrows"), but drawing one pointing away from the mirror is standard best practice.
❌ Common Diagram Mistakes
- Drawing the normal perpendicular to the paper edge rather than perpendicular to the mirror line.
- Drawing the reflected ray freehand without a ruler.
- Guessing the reflected angle by eye rather than measuring to make i = r.
Evaluating Experimental Methods: Method A vs Method B
Comparing Laser + Printed Protractor vs Ray Box + Single Slit
✅ Model Answer: Two Improvements Explained
- Advantage: The protractor is printed directly on the paper, so the mirror does not have to be moved to measure the angles (or the protractor does not need to be repositioned / no need to mark ray positions). [1 mark]
- Explanation: This avoids disturbing the mirror position, making the results more accurate and reducing random errors. [1 mark]
- Advantage: The laser ray in Method A does not diverge (it is much thinner / narrower than the beam from the ray box). [1 mark]
- Explanation: It is easier to identify and judge the exact centre (position) of the ray, leading to more accurate angle measurements. [1 mark]
🧠 Exam Technique: "Explain two ways..."
- Notice the question carries 4 marks for two ways. That means each way needs an identification (1 mark) AND an explanation of why that is better (1 mark):
Feature (1 mark) → Impact on accuracy / measurement (1 mark) - The mark scheme also accepts converse arguments detailing why Method B is worse:
• Ray box beam diverges/spreads out, making the centre hard to pinpoint.
• Having to place/move the handheld protractor can accidentally nudge the mirror or misalign the normal.
Topics
Physics · Required Practicals · P6: Waves · Required Practicals
Question and mark scheme from the AQA GCSE Physics examination, Physics Paper 2 (Higher), June 2022. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.