Edexcel A Level Physics:复习笔记5.3 Longitudinal Waves
Longitudinal Waves
Longitudinal Waves
- A longitudinal wave is one where the particles oscillate?parallel?to the;
- Propagation of the wave
- Direction of energy transfer
- Longitudinal waves show areas of
- High pressure,?called?compressions
- Low pressure, called?rarefactions
Diagram of a longitudinal wave
- Examples of longitudinal waves are:
- Sound waves
- Ultrasound waves
- P-waves caused by earthquakes
- Longitudinal waves?cannot?be?polarised
Labelling Longitudinal Waves
- You learned how to describe the properties of a wave, such as amplitude and wavelength at the start of this topic
- The diagram shows a wavelength on a longitudinal wave
Wavelength is shown on a longitudinal wave
Exam Tip
Questions about longitudinal waves typically start by asking for a definition, so be ready with a statement about areas of high and low pressure and the keywords compression and rarefaction.
Be careful with graphs of waves and don't assume a sinusoidal-shaped graph represents a transverse wave. Longitudinal waves can also look sinusoidal when plotted on a graph - make sure you read the question and look for whether the wave travels?parallel?(longitudinal) or?perpendicular?(transverse) to the direction of travel to confirm which type of wave it is.
转载自savemyexams
国际竞赛真题资源免费领取
美高学分项目重磅来袭！立即了解
