This topic summary covers Topic Summary: Sound Waves within Sound Waves for GCSE Physics. Revise Sound Waves in Waves for GCSE Physics with 13 exam-style questions and 15 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 13 of 13 in this topic. Use this topic summary to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 13 of 13
Practice
13 questions
Recall
15 flashcards
Topic Summary: Sound Waves
Key Terms
- Longitudinal: particles vibrate parallel to wave travel
- Compression: high-pressure region
- Rarefaction: low-pressure region
- Ultrasound: frequency > 20,000 Hz
- Infrasound: frequency < 20 Hz
Key Facts
- Sound speed: gas < liquid < solid
- Sound in air: ~330 m/s
- Cannot travel through vacuum
- Louder = bigger amplitude on oscilloscope
- Higher pitch = higher frequency on oscilloscope
Key Equations
- v = f × λ
- distance = (speed × time) ÷ 2 (echo)
- f = 1/T
Exam Tips
- Echo formula: always ÷2 for return journey
- Ultrasound = non-ionising = safe for foetuses
- Sound = longitudinal; EM waves = transverse
- Amplitude affects loudness; frequency affects pitch