AQA GCSE Physics Physics Paper 2 (Foundation), November 2021: Question 7
13 marks · Standard Demand difficulty · Short Answer
Analyze magnetic fields of bar magnets and electromagnets, and calculate the time taken for a conveyor belt carrying a can to travel a given distance.
Practise this questionQuestion
Question text
07 Figure 16 shows the magnetic field pattern around a bar magnet.
Figure 16
07.1 Draw an arrow at point A and point B to show the direction of the magnetic field at
each point.
[1 mark]
07.2 A bar magnet produces its own magnetic field.
Complete the sentence.
Choose the answer from the box.
[1 mark]
an electromagnet an induced magnet a permanent magnet
A bar magnet is an example of .
07.3 Which graph shows how the strength of the magnetic field varies with distance from
the bar magnet?
Give a reason for your answer.
[2 marks]
Tick ( ) one box.
Reason
Figure 17 shows an electromagnet being used to separate aluminium cans from
steel cans.
Figure 17
07.4 Explain how the electromagnet and conveyor belt are used to separate the steel cans
*31* from the aluminium cans.
[2 marks]
07.5 At the top of the table the strength of the magnetic field is only just enough to pick the
cans up.
Describe two ways to increase the strength of magnetic field at the top of
the table.
[2 marks]
07.6 Write down the equation which links distance travelled (s), speed (v) and time (t).
[1 mark]
07.7 The conveyor belt moves a can at a speed of 1.7 m/s.
Calculate the time taken to move the can 3.3 m at this speed.
Give your answer to 2 significant figures.
[4 marks]
Time taken (2 significant figures) = s
Mark scheme
Show the mark scheme
Question 7
AO /
Question Answers Extra information Mark
Spec. Ref.
07.1 both arrows correct 1 AO1
4.7.1.2
07.2 a permanent magnet 1 AO1
4.7.1.1
07.3 third box ticked 1 AO3
4.7.1.2
any one from 1
• (the only graph) that shows only scores if correct box is
the magnetic field getting chosen
weaker (as distance
increases)
• both other graphs show the
magnetic field getting stronger
(as the distance increases)
07.4 steel cans are attracted to the 1 AO1
electromagnet and are 4.7.1.2
transferred to the container (by
the conveyor belt)
aluminium cans are not 1
attracted to the electromagnet
and are left behind on the table
If no other mark scored:
Steel cans are attracted (to the
electromagnet) but aluminium
cans are not – scores one mark
07.5 raise the height of the table allow longer legs on the table 1 AO3
allow put a (non-magnetic) box 4.7.2.1
on top of the table
allow lower the electromagnet
use a larger potential difference allow more turns on the coil (of 1
/ current the electromagnet)
or
use a stronger electromagnet
do not accept insert a (soft) iron
core
07.6 distance travelled = speed × 1 AO1
time 4.5.6.1.2
or
s = v t
07.7 3.3 = 1.7 × t 1 AO2
4.5.6.1.2
t = 3.3 1
1.7
t = 1.941 (s) 1
t = 1.9 (s) allow a calculation using the 1
given data incorrectly but
correctly rounded to 2 sig figs
Total 13
How to answer it
GCSE Physics Study Guide: Magnetism & Speed Calculation
What this question tests
This question assesses your understanding of magnetic fields, permanent versus induced magnets, electromagnets and their practical applications, and core physics calculations involving distance, speed, and time. You will need to interpret magnetic field diagrams, graph relationships, and apply standard kinematic equations using correct significant figures.
Magnetic Field Direction
✅ Correct Answer
Arrows drawn on the magnetic field lines pointing:
- Point A: Pointing downwards and curving towards the South pole (S).
- Point B: Pointing to the left (from North to South, underneath the bar magnet).
💡 Key Knowledge
Magnetic field lines always run from the North (N) pole to the South (S) pole outside of a magnet. Arrows must be included to show this direction.
Types of Magnets
✅ Correct Answer
a permanent magnet
🧠 Exam Technique
Make sure to copy the exact phrasing from the provided answer box. Do not invent your own terms.
Magnetic Field Strength vs. Distance
✅ Correct Answer
Third graph ticked (curves downwards smoothly as distance increases).
Reason: The magnetic field gets weaker as the distance from the magnet increases (or conversely, the other graphs incorrectly show the field getting stronger with distance).
❌ Common Errors
Students often tick the correct graph but fail to give a valid comparative reason, or incorrectly state that distance has no effect on field strength.
Separating Materials Using an Electromagnet
✅ Correct Answer
- Steel cans are magnetic, so they are attracted to the electromagnet and carried away to the container.
- Aluminium cans are non-magnetic, so they are not attracted and are left behind on the table.
💡 Key Knowledge
Steel contains iron, making it a magnetic material. Aluminium is a non-magnetic metal and will not experience a magnetic force.
Increasing Electromagnet Strength
✅ Correct Answer
Any two of the following:
- Increase the potential difference / current through the coil.
- Use a stronger electromagnet (or increase the number of turns on the coil).
- Raise the height of the table / lower the electromagnet / put a non-magnetic box on the table to reduce the distance to the cans.
❌ Common Errors
Do not suggest inserting a soft iron core if the core is already fixed, or introducing answers that contradict the setup. Keep suggestions practical and physically valid.
Equation Linking Distance, Speed, and Time
✅ Correct Answer
distance travelled = speed × time
Or standard symbols: s = v × t
Calculation: Time Taken
📐 Step-by-Step Calculation
- State the equation: s = v × t
- Substitute values: 3.3 = 1.7 × t
- Rearrange for time (t): t = 3.3 / 1.7
- Calculate unrounded value: t = 1.94117... s
- Apply significant figures: Round to 2 significant figures to get 1.9 s
❌ Common Calculation Traps
Forgetting to round to the requested 2 significant figures will cost you the final accuracy mark, even if your initial working is completely correct!
Topics
Physics · P5: Forces · P7: Magnetism and Electromagnetism
Question and mark scheme from the AQA GCSE Physics examination, Physics Paper 2 (Foundation), November 2021. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.