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Question
The wave pattern on a stretched string is shown in figure. Interpret what kind of wave this is and find its wavelength.
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Solution
All particles are at rest at t = `T/4` and t = `(3T)/4`, which is in the stationary wave when the particle crosses its mean position.
Thus, the graph shows a stationary wave. The wave at x = 10, 20, 30, 40 cm there are nodes and the distance between successive nodes is `λ/2`.
∴ `λ/2 = (30 - 20)`
⇒ λ = 20 cm
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