Transverse & Longitudinal Waves | Physics for GCSE/IGCSE - Year 11 PDF Download

Introduction

• Waves are repeated vibrations that transfer energy. 
• Waves can exist as one of two types:
  • Transverse 
  • Longitudinal

Transverse Waves

• In transverse waves, points along their length oscillate perpendicular to the direction of energy propagation.
• Energy transfer occurs perpendicular to wave motion.
• They convey energy without displacing the particles of the medium.
• Transverse waves can traverse solids and liquid surfaces but not penetrate liquids or gases.
• Certain transverse waves, like electromagnetic waves, can propagate through solids, liquids, gases, and even vacuum.
• The highest point on the wave above the rest position is called the peak or crest, while the lowest point below the rest position is termed the trough.

• Examples of transverse waves include:
  • Ripples forming on the surface of water.
  • Vibrations occurring on a guitar string.
  • S-waves, a category of seismic wave.
  • Electromagnetic waves, encompassing radio waves, light, X-rays, and others.

Representing Transverse Waves

• Transverse waves are typically illustrated as a single, unbroken line.
• A central line indicates the undisturbed position.
• Curves on the diagram are drawn perpendicular to the direction of energy transfer.
  • These curves represent the peaks and troughs of the wave.

Longitudinal Waves

• Longitudinal waves are described as:
  • Waves in which points along their length oscillate parallel to the direction of energy propagation.
• Energy transfer occurs in the same direction as the wave's motion.
  • They transmit energy without displacing the particles of the medium.
  • Longitudinal waves can propagate through solids, liquids, and gases.
  • However, they cannot travel through a vacuum due to the absence of particles.
• Key characteristics of longitudinal waves include:
  • Regions where points are close together, termed compressions.
  • Regions where points are spaced apart, known as rarefactions.

• Examples of longitudinal waves include:
  • Sound waves.
  • P-waves, a category of seismic wave.
  • Pressure waves resulting from repetitive motions within a liquid or gas.

Representing Longitudinal Waves

• Longitudinal waves are commonly represented by multiple lines on a diagram.
• These lines indicate the wave's movement parallel to the direction of energy transfer.
  • Bringing the lines closer together on the diagram signifies compressions.
  • Conversely, spacing the lines further apart represents rarefactions.

Difference between Longitudinal and Transverse Waves

The different properties of transverse and longitudinal waves are shown in the table: