CBSE Class 10 Answered

The sounds of musical instruments which have the same pitch/frequency can be distinguished by the quality or timber of the sound which depends on
a) The number and frequency of the overtones(integral multiples of fundamental frequency) present in the given sound.
b)Relative intensity of the overtones.

The sounds of musical instruments will be associated with different number of overtones of different relative intensities.These overtones combine to produce different sounds which enables us to distinguish them.

For example, brass instruments tend to produce odd-integer harmonics while woodwind instruments tend to produce even integer harmonics.