Study Notes
Waves are disturbances that transfer energy through a medium without transferring matter. They can be transverse, like those on a rope, or longitudinal, like sound waves in air.
- Wave Speed — the rate at which energy moves through a medium. Example: Calculated using the formula wave speed = frequency × wavelength.
- Frequency — the number of oscillations per unit time. Example: Measured in Hertz (Hz).
- Wavelength — the distance between two consecutive points in phase on a wave. Example: Measured in meters (m).
- Amplitude — the maximum displacement from the equilibrium position. Example: Determines the loudness of sound.
- Reflection — when waves bounce off a surface. Example: Angle of incidence equals angle of reflection.
- Refraction — the bending of waves when entering a new medium. Example: Light bending when passing through a glass block.
- Diffraction — the spreading of waves around obstacles. Example: Water waves bending around a barrier.
Exam Tips
Key Definitions to Remember
- Wave speed is the distance a wave travels per second.
- Frequency is the number of waves passing a point per second.
- Wavelength is the distance between two consecutive points in phase.
- Amplitude is the maximum displacement from the rest position.
Common Confusions
- Mixing up transverse and longitudinal waves.
- Confusing wave speed with frequency.
Typical Exam Questions
- What is wave speed? Wave speed is the distance a wave travels in a given time, calculated as frequency multiplied by wavelength.
- How does refraction occur? Refraction occurs when a wave changes speed and direction as it enters a different medium.
- What happens during diffraction? Waves spread out as they pass through a gap or around an obstacle.
What Examiners Usually Test
- Understanding of wave properties and calculations.
- Ability to explain phenomena like reflection, refraction, and diffraction.
- Differences between transverse and longitudinal waves.