A certain transverse wave is described by y(x,t)=bcos[2π(xl−tτ)], where b = 6.80 mm , l = 30.0 cm , and τ = 3.90×10−2 s . Posted on September 6, 2021 | by wp A certain transverse wave is described by y(x,t)=bcos[2π(xl−tτ)], where b = 6.80 mm , l = 30.0 cm , and τ = 3.90×10−2 s .