1. A water wave has a speed of 1.0 m/s. The distance between crests is 0.5 m. What is the wavenumber of the wave? If an observer at a fixed location measures the height h(t) of the wave that passes by, what is the frequency of the signal h(t)? 2. k =2π/λ -> to get k= wavenumber h (t) = Acos (ωt − kz +φ) Hello, I need to do the above problem. I do have k( wavenumber). It's 12.56. I can move on to the second question now. The equation I would use is the second one above. ω = K*V. T should be 0. k is given now. How do I get A and φ ? It should be φ = −ψ. But I don't know how to get −ψ. ω could also be ω= 2πf But I don't know how to get f cause I don't have the Herz for the wave. I hope somebody can help me! Thank you!