An empty earthen pitcher is kept under a water tap and starts filling with water as the tap is opened. The pitch of the sound produced
(A) Goes on decreasing
(B) Goes on increasing
(C) First increases and then decreases after the pitcher is half filled
(D) Does not change

Hint:When we start filling the empty bucket with water the pitch of the sound produced goes on changing because the empty bucket here acts as a closed organ pipe.

Complete step by step answer:
We know that when the water in the earthen pitcher increases, the length of air inside the earthen pitcher decreases as there won’t be any much space left. As a result, the pitch of the sound will increase, that is, the sound becomes shriller because the frequency or pitch of sound is inversely proportional to the length of the vibrating air column. Also the amplitude of or the loudness of the sound will decrease, as the amount of the air column vibration decreases as the earthen pitcher fills up. We can also detect the earthen pitcher is filling up as there will be an increase in shrillness of the sound. The frequency of the fundamental frequency produced by the earthen pitcher would be given as
$n\:=\:\dfrac{v}{4l}$
Where,
n= frequency
l= length of the closed earthen pitcher
v = the speed of the sound wave
Considering the above information, we can conclude that when an empty earthen pitcher is kept under the water and starts filling with water and the tap is open, the pitch of the sound produced increases.

Thus, the correct answer is option B.

Note:The fundamental frequency which is also called natural frequency, and often called as fundamental is the lowest frequency of the periodic waveform. In music, the fundamental is the musical pitch of a note that is perceived as the lowest partial present. Since the fundamental is the lowest frequency and is also perceived as the loudest, the ear identifies it as the specific pitch of the musical tone.