AQA GCSE Combined Science: Trilogy Physics Paper 2 (Foundation), November 2020: Question 5
9 marks · Standard Demand difficulty · Short Answer
Identify wave properties from diagrams and calculate wave speed, period, and frequency from graphical data.
Practise this questionQuestion
Question text
05 Figure 6 shows four waves.
The waves are drawn to the same scale.
Figure 6
05.1 Which wave has the greatest amplitude?
[1 mark]
Tick ( ) one box.
A B C D
05.2 Which wave has the greatest frequency?
[1 mark]
Tick ( ) one box.
A B C D
05.3 Which wave has the greatest wavelength?
[1 mark]
Tick ( ) one box.
A B 16C D
05.4 A wave has a frequency of 1650 Hz and a wavelength of 0.200 m
Calculate the wave speed.
Use the equation:
wave speed = frequency × wavelength
[2 marks]
Wave speed = m/s
A student uses a mobile phone app that displays sound waves.
Figure 7 shows the student holding the mobile phone close to a loudspeaker.
Figure 7
Figure 8 shows the wave pattern seen on the phone screen.
Figure 8
05.5 What is the period of the wave shown in Figure 8?
[1 mark]
Tick ( ) one box.
0.002 s 0.004 s 0.006 s 0.008 s
05.6 Determine the frequency of the wave shown in Figure 8.
Use the Physics Equations Sheet.
[3 marks]
Frequency = Hz
Mark scheme
Show the mark scheme
AO /
Question Answers Extra information Mark
Spec. Ref.
05.1 A 1 AO1
6.6.1.2
05.2 B 1 AO1
6.6.1.2
05.3 D 1 AO1
6.6.1.2
05.4 v = 1650 × 0.200 1 AO2
6.6.1.2
v = 330 (m/s) 1
05.5 0.004 s 1 AO2
6.6.1.2
allow ecf from question 05.5
05.6 1 1 AO2
0.004 =
frequency 6.6.1.2
frequency =
0.004
F = 250 (Hz)
Total 9
How to answer it
Wave Features, Speed, and Frequency
What this question tests
- Visual wave features: Identifying amplitude, wavelength, and frequency by comparing wave traces drawn to the same scale.
- Wave speed formula: Applying wave speed = frequency × wavelength .
- Interpreting displacement-time graphs: Determining the time period ( T ) of a single complete wave oscillation.
- Period-frequency relationship: Selecting and rearranging period = 1 / frequency to calculate frequency in Hertz (Hz).
Parts 05.1, 05.2 & 05.3: Comparing Wave Traces
Identifying Wave Characteristics from Diagrams
✅ Correct Answers
- 05.1 Greatest Amplitude: A [1 mark]
- 05.2 Greatest Frequency: B [1 mark]
- 05.3 Greatest Wavelength: D [1 mark]
💡 Key Knowledge
- Amplitude: The maximum displacement of a point on a wave from its undisturbed position (the height from the middle line to the crest or trough). Wave A is the tallest.
- Frequency: The number of complete waves passing a point each second. Wave B has the most cycles packed into the same space.
- Wavelength: The distance between two matching points on adjacent cycles (e.g. peak to peak). Wave D has the widest, most stretched-out single cycle.
🧠 Exam Technique
Always inspect the axis and scale. Since all four traces are drawn to the same scale:
- Tallest trace = greatest amplitude.
- Most crowded waves = highest frequency.
- Widest spread per cycle = longest wavelength.
❌ Common Errors
- Measuring amplitude from peak to trough instead of from the middle line to peak.
- Confusing frequency (how squashed together the waves are) with wavelength (the width of one wave). High frequency means short wavelength!
Part 05.4: Calculating Wave Speed
Applying the Wave Equation [2 marks]
📐 Step-by-Step Calculation
Given:
- Frequency ( f ) = 1650 Hz
- Wavelength ( λ ) = 0.200 m
- Equation: v = f × λ
Step 1: Substitute the values into the formula
v = 1650 × 0.200
Step 2: Calculate the final answer
v = 330 m/s
✅ Mark Scheme Breakdown
- 1st Mark: Correct substitution: 1650 × 0.200
- 2nd Mark: Correct calculation: 330 (m/s)
❌ Common Trap
Dividing instead of multiplying. The formula was given directly in the question: wave speed = frequency × wavelength . Always write out your substitution step clearly to secure the method mark even if you make a calculator slip.
Part 05.5: Determining Period from a Graph
Reading Displacement-Time Waveform Displays [1 mark]
✅ Correct Answer
0.004 s
💡 Key Knowledge
The period is the time taken for one complete cycle of an oscillation.
- A full wave consists of one crest + one trough.
- The wave starts at 0 s , rises to a peak, passes the centre line at 0.002 s (half a wave), goes through a trough, and returns to the centre line moving upwards at 0.004 s .
- Therefore, 1 complete cycle takes 0.004 s.
❌ Common Misconception
Many students choose 0.002 s because they stop when the wave first hits the axis. That is only half of a wave! Always trace a full crest AND a full trough to find the period.
Part 05.6: Calculating Frequency from Period
Selecting & Rearranging the Equation [3 marks]
📐 Step-by-Step Calculation
Step 1: Select the equation from the Physics Equations Sheet
period = 1 / frequency or T = 1 / f
Step 2: Substitute your value for period (from 05.5)
0.004 = 1 / frequency [1 mark]
Step 3: Rearrange to make frequency the subject
frequency = 1 / 0.004 [1 mark]
Step 4: Solve
frequency = 250 Hz [1 mark]
🧠 Exam Technique & ECF
- Error Carried Forward (ECF): If you chose an incorrect period in 05.5 (e.g. 0.002 s), you can still gain all 3 marks here if you correctly calculate 1 / 0.002 = 500 Hz !
- Rearrangement Rule: If A = 1 / B , then B = 1 / A . The unknown and the denominator simply swap places.
- Remember the unit for frequency is Hertz (Hz), which means "cycles per second".
✅ Final Answer
Frequency = 250 Hz
Topics
Physics · P6: Waves
Question and mark scheme from the AQA GCSE Combined Science: Trilogy examination, Physics Paper 2 (Foundation), November 2020. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.