A wave is represented by the equation y = 10 sin 2π(100t - 0.02x) + 10 sin 2π(100t + 0.02x). The maximum amplitude and loop length are respectively:
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A wave is represented by the equation y = 10 sin 2π(100t − 0.02x) + 10 sin 2π(100t + 0.02x). The maximum amplitude and loop length are respectively:

G1 Physics · Accepted Answer

Step 1: Add the counter-propagating waves: y = 20 sin(200πt) cos(0.04πx). Step 2: Maximum standing-wave amplitude is 20. Here k = 0.04π, so λ = 2π/k = 50 and loop length = λ/2 = 25. Final: B.