Basics of Waves

Key Concepts

• Energy Transfer: Waves transfer energy without transferring matter.
  • Examples: Light waves from a screen to the eye, sound waves from speakers to the ear.
• Oscillation: Waves vibrate or oscillate to travel from one place to another.

Wave Parts

• Displacement-Distance Graph:

  • Displacement: Distance from the equilibrium point (how far up or down the wave oscillates).
  • Amplitude: Maximum displacement from the equilibrium.
  • Wavelength: Distance of one complete oscillation (equilibrium up, down, back up, or crest to crest).
  • Crest: The top of the wave.
  • Trough: The opposite of the crest.

• Displacement-Time Graph:

  • Time Period: Time for one complete oscillation (used instead of wavelength).

Calculating Frequency

• Frequency: Number of complete oscillations per second (measured in Hertz, Hz).
  • Equation: Frequency = 1 / Time Period
  • Example: If time period = 0.5 seconds, frequency = 2 Hz.

Calculating Wave Speed

• Wave Speed Equation: Wave Speed = Wavelength x Frequency
  • Example:
    • Frequency = 400 Hz
    • Wavelength = 70 cm (converted to 0.7 m)
    • Wave Speed = 0.7 m x 400 Hz = 280 m/s

Types of Waves

Transverse Waves

• Oscillations are perpendicular to the direction of energy transfer.
• Examples: Electromagnetic waves (light, radio), water ripples, string vibrations.

Longitudinal Waves

• Oscillations are parallel to the direction of energy transfer.
• Features areas of compression and rarefaction.
• Examples: Sound waves, seismic P waves.

This concludes the overview of wave basics, including parts of a wave, how to calculate wave properties, and the differences between transverse and longitudinal waves.