Stationary waves, strings and pipes
Watch the whole lecture free
Make a free account to watch every lecture to the end: 3 practice questions, 5 real past-paper questions with the answers explained, the mistakes that lose marks, the full-marks tip, a one-card summary and a quick quiz.
That was the teaching part. The rest of this lecture is free with an account: 3 practice questions, 5 real past-paper questions with the answers explained, the mistakes that lose marks, the full-marks tip, a one-card summary and a quick quiz.
No password needed now: we email you a link to set one. Already have an account? Sign in, then come back to this page.
The teaching part (1 min) is free to watch. A free account opens the whole lecture: 3 practice questions, 5 real past-paper questions with the answers explained, the mistakes that lose marks, the full-marks tip, a one-card summary and a quick quiz.
What this lecture covers
- A guitar string and a pipe
- What is a stationary wave?
Read the transcript of the teaching part
Last time
Before we start: last time, in Superposition and interference, you learned these points. Here they are again on one card. Keep them in mind, because today builds on them.
A guitar string and a pipe
Pluck a guitar string, and it vibrates in a smooth shape that seems to stand still. Blow across a bottle, and you hear a clear note. Both are stationary waves: waves reflecting back on themselves, and adding up into a pattern that does not travel.
What is a stationary wave?
A stationary wave is formed when two progressive waves of the same type, frequency and amplitude travel in opposite directions and superpose. It forms, for example, when a wave is reflected back along the same string or tube. It does not transfer energy along the string. The pattern stays in place. They must travel in opposite directions. Travelling in the same direction would not form a stationary wave.
How often it comes up
How often Cambridge has asked each part, counted by ExamYard from every past paper in its question bank: Stationary waves in pipes · Stationary waves · Stationary waves.
The whole chapter: Superposition, Superposition.
Chapter 8.3: Stationary waves
- Stationary waves, strings and pipes 6 min
Also for A Level Physics 9702
Which topics come up most in A Level Physics 9702 past papers, counted from every paper since 2004: Paper 1 topic frequency, Paper 2 topic frequency.