試題詳解

(7)The waves are a cosine curve with crests 18 m apart. A vertical distance 4.8 m from trough to crest, which takes 1.7 s. Please describe the wave.
(A)y(x,t) = 4.8cos(0.70x – 3.70t)
(B)y(x,t) = 2.4cos(0.35x - 1.85t)
(C)y(x,t) = 2.4cos(0.52x – 1.70t)
(D)y(x,t) = 4.8cos(0.35x - 1.85t)
(E)y(x,t) = 2.4cos(0.28x – 1.32t)