Correct option is B
The loudness of a sound wave is directly related to its amplitude. Amplitude refers to the maximum displacement of particles from their equilibrium position in a medium through which the sound is traveling. The greater the amplitude of the wave, the louder the sound is perceived.
Loudness is a subjective sensation but depends on the energy of the wave, which increases with amplitude. Higher amplitude waves carry more energy, leading to louder sounds, while lower amplitude waves produce softer sounds.
Information Booster
- Amplitude and Loudness Relationship:
- Loudness ∝ Amplitude² (Loudness increases with the square of amplitude).
- Unit of Loudness: Measured in decibels (dB).
- Factors Affecting Loudness:
- Energy of the sound wave.
- Distance from the source (loudness decreases with distance).
- Other Properties of Sound Waves:
- Frequency determines the pitch.
- Wavelength affects the tone.
- Speed depends on the medium.
Additional Knowledge
- (a) Speed – Incorrect. Speed determines how fast a sound wave travels through a medium but does not affect loudness.
- (b) Amplitude – Correct. Loudness is proportional to the amplitude of the sound wave.
- (c) Wavelength – Incorrect. Wavelength is related to the distance between consecutive wave crests and does not determine loudness.
- (d) Frequency – Incorrect. Frequency determines the pitch of the sound, not its loudness.