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QNEET-2018-Ph-889: NEET 2018 Physics - Class 11 NEET-2018-Ph-889 Solution: The fundamental frequency in an open organ pipe is equal to the …
The fundamental frequency in an open organ pipe is equal to the third harmonic of a closed organ pipe. If the length of the closed organ pipe is 20 cm the length of the open organ pipe is 13.2 cm 8 cm 12.5 cm 16 cm
Multiple Choice Options
- A 13.2 cm
- B 8 cm
- C 12.5 cm
- D 16 cm
Step-by-Step Verified Solution
For closed organ pipe, third harmonic
n = ( 2 N _ 1 ) V 4 l = 3 V 4 l ( _ N = 2 )
For open organ pipe, fundamental
frequenty
n = N V 2 l = V 2 l _ ( _ N = 1 )
Given, third harmonic for closed organ pipe
= fundamental frequency for open organ pipe.
_ 3 V 4 l = V 2 l _
_ l' = 4 l 3 _ 2 = 2 l 3 = 2 _ 20 3 = 13.33 cm