A person strikes a piano key softly at first and then strikes the same key much harder. What changes will be observed in the characteristics of the sound in the second case?

When a longitudinal sound wave propagates through air, what happens at a region of compression?

The loudness of sound depends on the amplitude of vibration such that loudness is:

Consider the following statements: 1. The loudness of a sound is determined basically by its frequency. 2. The frequency of the sound wave does not change when it travels from one medium to another. 3. Audible range of the average human ear extends from about 20 Hz to 20 kHz. How many of the statements given above are correct?