Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NEET 2018
Exam
NEET
Year
2018
Subject
Physics
Chapter
Waves and Sound

NEET 2018 · Physics · Waves and Sound

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 closed organ pipe. If the length of the closed organ pipe is 20 cm, the length of the open organ pipe is

Options

  1. A12.5cm12 . 5cm
  2. B8cm8cm
  3. C13.2cm13 . 2cm
  4. D16cm16cm

Correct answer

C. 13.2cm13 . 2cm

Step-by-step solution

For closed organ pipe, third harmonic 3v4lcop\dfrac{3v}{4{l}_{cop}}
For open organ pipe, fundamental frequency v2loop\dfrac{v}{2{l}_{oop}}.

According to question

foop=3fcop{f}_{oop} = 3{f}_{cop}

⇒v2loop=3v4lcop⇒ \dfrac{v}{2{l}_{oop}} = \dfrac{3v}{4{l}_{cop}}

loop=23×lcop=23×20≈13.2cm{l}_{oop} = \dfrac{2}{3} \times {l}_{cop} = \dfrac{2}{3} \times 20 \approx 13.2\text{c}\text{m}

Practice Waves and Sound on Quantrex Academy →

More from Waves and Sound

For the given wave equation y = 10 π((x)/(4) + (t)/(2)) , the CORRECT statement is (… MHT CET Medical 2026The source is emitting sound of frequency 'n'. A source and a listener both are moving… MHT CET Medical 2026Two uniform strings X and Y made of same material made to vibrate under same tension. If… MHT CET Medical 2026A simple harmonic progressive wave is represented as Y = 0.04 π (2t - 0.02x) m. At a… MHT CET Medical 2026Two waves having same amplitude A , angular frequency ω and propagation constant k… MHT CET Medical 2026Identify the CORRECT statement on beats (A) The amplitude of beats is always constant.… MHT CET Medical 2026An organ pipe closed at one end produces 5^ th overtone of an air column. It is found… MHT CET Medical 2026The speed of the transverse wave on the stretched string under tension T_1 is v_1 . If… MHT CET Medical 2026 Full Waves and Sound list All NEET PYQs