Quality of a musical note depends on

In an orchestra,the musical sounds of different instruments are distinguished from one another by which of the following characteristics?

The tones that are separated by three octaves have a frequency ratio of

Out of the following musical instruments, which is '$NOT$' a percussion instrument?

$A$ hearing test is conducted on an aged person. It is found that her threshold of hearing is $20 \, dB$ at $1 \, kHz$ and it rises linearly with frequency to $60 \, dB$ at $9 \, kHz$. The minimum intensity of sound that the person can hear at $5 \, kHz$ is

Learned Indian classical vocalists do not like the accompaniment of a harmonium because