Which physical parameters does the harmful effect of noise depend on

• A. Intensity
• B. Frequency
• C. Both intensity and frequency
• D. Duration

Answer: (C)

The amount of harm from noise depends on how much energy reaches the ear and how that energy is distributed across frequencies. Intensity sets the overall energy delivered—the louder the sound, the greater the potential for damage. Frequency content matters because the ear and cochlea respond differently to different frequencies; certain bands can cause more stress to specific hair cells and lead to greater risk of damage at those frequencies. While exposure duration also influences risk in real life, the question targets the inherent physical properties of the noise, so both intensity and frequency together best explain the potential harm.