Waves

Waves - Basics

• Definition: A wave is a disturbance traveling through a medium from one location to another, transferring energy through vibration.

Types of Waves

• Two main types of waves:

  • Longitudinal waves

  • Transverse waves.

Wave Movement

• Transverse Waves: Hand moves up and down repeatedly.

• Longitudinal Waves: Hand moves backward and forward along the line of a slinky.

Transverse Waves

• Travel in a direction perpendicular to vibration direction.

Examples of Transverse Waves

• Ocean waves

• Rope waves

• Light waves

• Seismic waves (S waves from earthquakes).

Longitudinal Waves

• Travel parallel to vibration direction.

Examples include:

• Sound waves

• P seismic waves (P waves from earthquakes).

Characteristics of Waves

• Important characteristics:

  • Crests and troughs

  • Amplitude

  • Wavelength

  • Frequency

  • Period

  • Speed.

Crests and Troughs

• Crests: High points (peaks) of a wave.

• Troughs: Low points (valleys) of a wave.

Amplitude

• Definition: Height of a crest or depth of a trough from a 'normal' undisturbed position.

• Measured in meters (SI unit).

Wavelength

• Definition: Distance between two successive peaks or troughs.

• Also measured in meters (SI unit).

Frequency

• Definition: Number of vibrations per second.

• Measured in Hertz (Hz):

  • 1 Hz = 1 vibration/second,

  • Example: 50 Hz = 50 vibrations/second.

Period

• Definition: Time taken for one complete vibration.

• Measured in seconds.

Period vs Frequency

• Relationship: Example: Wave with 100 Hz frequency = 1/100 seconds period.

• Frequency (Hz) and Period (s) chart provided.

Speed of Waves

• Definition: Distance a wave travels in one second.

• SI unit: meters per second (m/s).