AQA GCSE Physics Physics Paper 2 (Higher), June 2024: Question 6

✅ Correct Answers (Any 3)

• They travel at the same speed (in a vacuum/air, or the speed of light).
• They can travel through a vacuum.
• They are transverse waves.
• They are electromagnetic waves.

💡 Key Knowledge

All electromagnetic waves share a fundamental family of properties. They are all transverse, can travel through a vacuum (they do not need a medium), and travel at the exact same constant speed through a vacuum ( 3 × 10⁸ m/s ).

🧠 Exam Technique

Make sure your points are distinct. Writing "they are both waves" is too vague and will not gain credit. You must specify they are transverse or electromagnetic.

❌ Common Errors

Students often lose marks by listing properties that differ between them, such as frequency, wavelength, or ionising power, instead of focusing on what they have in common.

✅ Correct Answers (Any 1)

• Medical imaging (e.g., PET scan, using gamma-emitting tracers).
• Medical treatments (e.g., radiotherapy, treating cancer cells, gamma knife).
• Sterilising medical equipment.

❌ Common Errors

Do not accept: Ultrasound, CT scans, X-rays, or MRI scans—these use completely different types of radiation or technology. Also, do not confuse radiotherapy with chemotherapy (which is chemical, not radiological).

✅ Correct Answers (2 marks)

• Mark 1: Gamma rays are ionising, whereas radio waves are not ionising.
• Mark 2: (Because they are ionising) gamma rays can cause mutations in genes/DNA or increase the risk of cancer / damage cells.

💡 Key Knowledge

High-frequency electromagnetic waves (ultraviolet, X-rays, and gamma rays) carry high amounts of energy and are ionising. Low-frequency waves (radio, microwave, infrared) carry low energy and are non-ionising.

🧠 Exam Technique

This is a two-part causal explanation ("Explain why..."). You must link the physical property (ionising nature) directly to the biological consequence (cell damage or cancer risk) to secure both marks.

✅ Correct Answers (2 marks)

• Mark 1: Radio waves are produced by oscillations in electrical circuits (or alternating current / oscillating electrons in an aerial).
• Mark 2: The frequency of the radio waves produced is the same as the frequency of the electrical oscillations.

💡 Key Knowledge

Radio waves can be produced by, or can themselves induce, oscillations in electrical circuits. When charge oscillates back and forth in an alternating current circuit, it produces radio waves with a frequency matching that alternating current.

🧠 Exam Technique

Note the conditional dependency in the mark scheme: Mark 2 is dependent on Mark 1. You must first state that radio waves are created by circuit oscillations before you can score the mark for matching frequencies.

❌ Common Errors

Students frequently mention "vibrations" generally rather than specifically referring to oscillations in electrical circuits or alternating current, losing the first marking point.