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(Solved): 3) The dispersion equation for linear waves has the expression below 2=gktanh(kh) where =2/Tp ...
3) The dispersion equation for linear waves has the expression below ?2=gktanh(kh) where ?=2?/Tp? is angular frequency, Tp? is wave period, k=2?/L is wave number, L is wave length, and h is water depth. Note that wave (form) travel speed c=L/Tp?=?/k. Two approximation methods to solve k (given frequency ? and depth h ) by Guo (2002) and Beji (2013) are given below. (a) Guo's (2002) approximation k=ko?/[1?1/exp(x1.25)]0.4, where x=ko?h (b) Beji's (2013) approximation k=ko?[1+exp(1.1+2ko?h)(ko?h)1.3?]/tanh(ko?h)? (i) Given Tp?=5sec,h=10m, use MATLAB to calculate L using Methods (a) and (b). The true L (based Newton-Raphson Method) is ?36.563m. Is the estimate from (a) better than (b)? (ii) Given Tp?=5sec,h=3m, calculate L using Methods (a) and (b). The true L (based Newton-Raphson Method) is ?24.917m. Is the estimate from (a) better than (b) ? (iii) Based on the linear wave dispersion equation, wave (form) travel speed can be expressed as c=co?tanh(kh), where co?=gTp?/2?. Does the wave in (i) travel faster than the wave in (ii)?