Wave Mechanics Question 645
Question: The number of possible natural oscillation of air column in a pipe closed at one end of length 85 cm whose frequencies lie below 1250 Hz are: (velocity of sound $ =340m{{s}^{-1}} $ )
Options:
A) 4
B) 5
C) 7
D) 6
Show Answer
Answer:
Correct Answer: D
Solution:
[d] In case of closed organ pipe frequency, $ f _{n}=(2n+1)\frac{v}{4l} $ For $ n=0,,f _{0}=100Hz $
$ n=1,,f _{1}=300Hz $
$ n=2,,f _{2}=500Hz $
$ n=3,,f _{3}=700Hz $
$ n=4,,f _{4}=900Hz $
$ n=5,,f _{5}=1100Hz $
$ n=6,,f _{6}=1300Hz $ Hence possible natural oscillation whose frequencies < 1250 Hz=6(n= 0, 1, 2, 3, 4, 5)
BETA
