Q. In a closed organ pipe, the 1$^{st}$ resonance occurs at 50 cm. At what length of pipe, the 2$^{nd}$ resonance will occur
A) $150\ cm$
B) $50\ cm$
C) $100\ cm$
D) $200\ cm$
Explanation
(a) For a closed pipe, 1$^{st}$ resonance occurs at
$L_{1} = \frac{\lambda}{4} = 50\ cm$
2$^{nd}$ resonance occurs at
$L_{2} = \frac{3\lambda}{4} = 3\left( \frac{\lambda}{4} \right) = 3 \times 50cm = 150cm$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.