• summary_type: application
• word_count: 150

A tuning fork of frequency f is held over a tube with adjustable water level. Resonance (loud sound) occurs at: l_1 + e = lambda/4 (first), l_2 + e = 3lambda/4 (second). Taking the difference: lambda = 2(l_2 - l_1), eliminating end correction e. Speed: v = flambda = 2f*(l_2 - l_1). End correction: e = (l_2 - 3l_1)/2 ≈ 0.3d (tube diameter). Verification: l_3 - l_2 should equal l_2 - l_1 = lambda/2. Speed of sound depends on temperature: v = 331 + 0.6*T(degrees C) m/s. The resonance tube works with open-end correction — the antinode forms slightly outside the tube. For accurate results, use a narrow tube (smaller end correction) and bring the tuning fork close to the tube opening without touching. JEE may ask for end correction calculation or speed of sound at a given temperature.