Study Notes
Waves can be transverse or longitudinal, with energy moving through a medium at a speed determined by frequency and wavelength. Transverse waves have perpendicular displacement to wave direction, while longitudinal waves have parallel displacement.
- Amplitude — The maximum displacement shown by the particles taking part in the wave motion. Example: The height of a wave crest in water.
- Wavelength — The distance between one particle and the closest next particle in the same state of motion. Example: The distance between two consecutive crests in a water wave.
- Frequency — Number of oscillations produced by a particle in a unit time. Example: The number of waves passing a point per second.
- Speed — A wave travels a distance equal to a wavelength in a time interval equal to a period. Example: Calculated as frequency multiplied by wavelength, v = fλ.
- Doppler Effect — The apparent change in wavelength and frequency of a wave emitted by a moving source. Example: The change in pitch of a siren as an ambulance passes by.
Exam Tips
Key Definitions to Remember
- Amplitude: Maximum displacement of particles in wave motion.
- Wavelength: Distance between consecutive particles in the same motion state.
- Frequency: Number of oscillations per unit time.
- Speed: Product of frequency and wavelength, v = fλ.
- Doppler Effect: Change in wavelength and frequency due to a moving source.
Common Confusions
- Confusing transverse and longitudinal wave directions.
- Mixing up units for wavelength and speed.
- Misunderstanding the Doppler Effect's impact on frequency and wavelength.
Typical Exam Questions
- What is the difference between transverse and longitudinal waves? Transverse waves have perpendicular displacement; longitudinal waves have parallel displacement.
- How do you calculate wave speed? Wave speed is calculated using v = fλ.
- What happens to a wave when it refracts? Its speed and wavelength change, but frequency remains the same.
What Examiners Usually Test
- Understanding of wave properties and equations.
- Ability to differentiate between wave types.
- Application of the Doppler Effect in real-world scenarios.