Speed Of Sound In Air Using Resonance Tube — the NEET Physics formula with its derivation, variables, validity constraints and worked solver.
Speed of sound in air using Resonance Tube Used in lab settings to determine speed of sound using a resonance column apparatus where the tube is closed at one end by water level. First resonance occurs at l 1 + e = lambda/4 Second resonance occurs at l 2 + e = 3 lambda/4 Subtracting equations eliminates end correction (e): l 2 - l 1 = lambda/2 Substitute lambda = v/f into the equation: l 2 - l 1 = v/(2f) Rearrange for v: v = 2f(l 2 - l 1) Assumes constant temperature throughout the experiment Diameter of the tube must be uniform Assumes the same end correction for both resonance positions Thinking that l 2 is exactly 3 times l 1; this is false due to end correction (e). Only (l 2 - l 1) accurately represents half a wavelength. Forgetting that speed of sound is temperature dependent; lab results should be corrected to STP if required.