J & K CET Medical
J & K - CET Medical Solved Paper-2000
question_answer
A cylindrical tube open at both ends has a fundamental frequency \[f\] in air. The tube is dipped vertically in water, so that half of it is in water. The fundamental frequency of the air column is now:
A)\[\frac{f}{2}\]
B)\[\frac{3f}{4}\]
C)\[f\]
D)\[2f\]
Correct Answer:
C
Solution :
When length of open tube is\[l,\]then fundamental frequency \[n=\frac{v}{\lambda }=\frac{v}{2l}\] When dipped in water, \[n=\frac{v}{\lambda }\] Given, \[\frac{l}{2}=\frac{\lambda }{4}\] \[\therefore \] \[n=\frac{v}{2l}=n\] Given, \[n=f\] \[\therefore \] \[n=f\]