AQA GCSE Physics Physics Paper 1 (Higher), June 2022: Question 5

10 marks · Standard Demand difficulty · Short Answer

Explain static electricity concepts including charging by friction, electrostatic forces between like charges, zero errors in experiments, and sparks caused by potential difference.

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Question

Question text

05 A student rubbed a plastic rod with a cloth.

The rod became negatively charged and the cloth became positively charged.

05.1 Explain why the cloth became positively charged.

[3 marks]

Figure 6 shows the negatively charged rod on a balance.

Figure 6

Figure 7 shows another charged rod being held stationary above the rod on the

balance.

The rods do not touch each other.

Figure 7

100.35 g

05.2 Explain why the reading on the balance increases.

[3 marks]

05.3 The balance had a zero error.

The zero error is not important in this experiment.

Give the reason why.

[1 mark]

05.4 A negatively charged rod is held near an earthed conductor.

Explain why a spark jumps between the negatively charged rod and the earthed

conductor.

[3 marks]

Mark scheme

Show the mark scheme

AO /

Question Answers Extra information Mark

Spec. Ref.

any mention of transfer of

05.1 positive charge scores 0 AO1

4.2.5.1

any mention of positive

electrons scores 0

electrons transferred from the 1

cloth (to the rod)

electrons are negatively charged this mark only scores if linked to 1

the first marking point

(so) there are more positive ignore more protons than 1

charges than negative charges electrons unqualified

on the cloth

AO /

Spec. Ref.

05.2 there is an additional 1 AO3

(downwards) force on the

balance (increasing the mass

reading) AO3

(because) the (held) rod is allow both rods have the same 1

negatively charged (negative) charge AO1

(and rods with) like charges 1 4.2.5.1

repel

(and rods with) negative

charges repel each other

AO /

Spec. Ref.

05.3 only the change in reading / allow difference / increase for–HYSICS – 1 – AO3

mass is being observed ‘change in’ 4.2.5.1

AO /

Spec. Ref.

05.4 the (large) potential difference allow (strong) electric field 1 AO1

between the two objects causes breakdown of air 4.2.5.2

do not accept earthed conductor

is positively charged

(causes negative) electrons / allow there is a current in the air 1

charges to move (through the (between the two objects)

air)

(from the rod) to the conductor 1

– HYSICS – –

Total Question 5 10

Question 6

How to answer it

Static Electricity and Charge Interactions

What this question tests:
This question assesses your understanding of electrostatic charge, the transfer of electrons via friction, non-contact forces between like charges, zero errors in measurement, and electrical breakdown (sparks) caused by high potential differences.

Question 05.1

Explaining Charging by Friction

Explain why the cloth became positively charged. [3 marks]

✅ Correct Answer Structure

Electrons are transferred from the cloth to the rod.
Electrons are negatively charged.
Leaving more positive charges (protons) than negative charges on the cloth.

💡 Key Knowledge

Only electrons move during static charging (protons are fixed in the nucleus).
Gaining electrons makes an object negative; losing electrons makes it positive.

❌ Common Errors

Mentioning the transfer of "positive charge" or "positive electrons" instantly scores 0 marks.
Failing to explicitly link the loss of negative electrons to an excess of positive charge.

Mark breakdown: 1 mark for electron transfer direction + 1 mark for identifying electrons as negative + 1 mark for the resulting positive imbalance.

Question 05.2

Non-Contact Forces and Balance Readings

Explain why the reading on the balance increases. [3 marks]

✅ Correct Answer Structure

There is an additional downward force on the balance, increasing the mass reading.
The held rod is negatively charged (and the rod on the balance is also negative).
Like charges repel each other, pushing the bottom rod downwards.

🧠 Exam Technique

Link the observation (balance reading up) to a physical cause (downward force).
Always state the property of the charges involved (e.g., "both are negative" and "like charges repel").

Mark breakdown: 1 mark for identifying an additional downward force / increased mass reading + 1 mark for stating both rods are negatively charged + 1 mark for stating like charges repel.

Question 05.3

Zero Errors in Experiments

The balance had a zero error. The zero error is not important in this experiment. Give the reason why. [1 mark]

✅ Correct Answer Structure

Only the change in reading / mass is being observed.

💡 Key Knowledge

A zero error shifts all readings by a fixed amount. If you are only measuring a difference (final minus initial), the absolute starting offset cancels out entirely.

Mark breakdown: 1 mark for stating that only the change/difference in mass is measured.

Question 05.4

Electrical Sparks and Potential Difference

Explain why a spark jumps between the negatively charged rod and the earthed conductor. [3 marks]

✅ Correct Answer Structure

There is a large potential difference between the two objects.
This causes electrons/charges to move through the air.
The movement is from the rod to the conductor.

💡 Key Knowledge

Sparks happen when a strong electric field causes the surrounding air to break down and become conducting, allowing a current of electrons to flow rapidly.

❌ Common Errors

Stating that the earthed conductor is positively charged (it is neutral/earthed, but experiences induced charge separation).

Mark breakdown: 1 mark for large potential difference / strong electric field + 1 mark for electrons/charges moving through the air + 1 mark for direction (from rod to conductor).

Topics

Physics · P2: Electricity

Question and mark scheme from the AQA GCSE Physics examination, Physics Paper 1 (Higher), June 2022. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.