Question

For a resonance tube the air columns for the first and the second resonance are 24.5 and 75 cm. The wavelength of the sound wave is

• A. 202 cm
• B. 50.5 cm
• C. 101 cm
• D. 98 cm

Answer 1

Answer: (C)

101 cm

Let $l_1$ and $l_2$ be the lengths of the air column for first and second resonance in a resonance tube and $\lambda$ be the wavelength of the wave.

Thus $l_2-l_1=\frac{\lambda }{2}$

$(75-24.5)cm=\frac{\lambda }{2}⟹\lambda =101cm$