Question

A key of a mechanical piano struck gently and then struck again but much harder this time. In the second case

• A. sound will be louder but the pitch will not be different.
• B. sound will be louder and the pitch will also be higher.
• C. sound will be louder but the pitch will be lower.
• D. both loudness and the pitch will remain unaffected.

Answer 1

The correct option is A

sound will be louder but the pitch will not be different.

The explanation for the correct option.

Option A:

1. The pitch of the sound can be defined as the rate of vibration of the vocal folds.
2. The pitch changes as the frequency of the sound changes.
3. As the same key is struck thus, the pitch will be the same.
4. As the key is struck harder, the sound will be louder.
5. And Loudness of a wave is determined by the amplitude of the wave.
6. The loudness of a wave $\propto$ Amplitude of the wave.

The explanation for the incorrect options

For option (B), the pitch will not be higher as the same key is struck.

For option (C), the pitch will not be lower as the same key is struck.

For option (D), the loudness will be higher as the key is struck harder.

Hence, the correct option is (A).