A travelling wave moving from left to right has an amplitude of 0.15m, a frequency of 550Hz and a wavelength of 0.01m. The equation describing the wave is
A. y = 0.15 sin 200Ï€(x - 5.5t) B. y = 0.15 sin π(0.01x - 5.5t) C. y = 0.15 sin 5.5Ï€(x - 200t) D. y = 0.15 sin Ï€(550x - 0.01t)
Correct Answer: A
Explanation
The general wave equation is given by Y = sin A 2π/λ [x - vt] = Sin A [(2π X)/λ - (2π vt)/λ] thus if A = 0.15;λ = 0.01m; f = 550Hz then V = f x λ = 550 x 0.01 = 5.50m/s ∴ Y = 0.15 sin [(2 x λ x X)/0.01 - (2 x λ x 5.5t)/0.01] = 0.15 sin[200λX - 200 x λ x 5.5t] ∴ Y = 0.15 sin 200λ[x - 5.5t]
