CBSE Class 8 Answered

Amplitude:

The magnitude of the maximum disturbance in the medium on either side of the mean value is called the amplitude of the wave. The term amplitude is used to describe the size of the wave.

The loudness or softness of a sound is determined by its amplitude.

 

Pitch or shrillness :

Pitch is another characteristic of sound waves. It allows distinguishing between two sound waves travelling with the same speed and arriving at our ears at the same time.Example: We can distinguish between a man's voice and a woman's voice even without seeing them. This is because the man's voice and a woman's voice differ in their pitch. Pitch refers only to musical sounds, and each musical note has a definite pitch. If the pitch is higher, then the sound is said to be shrill. If the pitch is lower, then the sound is flat. 

Example: The membrane of a drum vibrates with a low frequency, therefore, a drum produces a low-pitched sound.

 

On the other hand, the air in a whistle vibrates with high frequency due to which the whistle produces a sound having a higher pitch.