A transverse traveling wave on a string starts at x = 0 and travels towards x = ∞. The wave has an amplitude of 1.20 m, wavelength of 4.60 m and travels at a speed of 14.3 m/s . At time t = 0.0 s the displacement at position x = 0.0 m is 1.20 m.
(b) Calculate the displacement at position x = 2.6 m when t = 8.60 s.
An identical wave is launched on a new string, whose mass per unit length doubles at some position x > 0.
(c) Determine wavefunctions for the reflected and transmitted waves. You do not need to consider their amplitudes.
The Attempt at a Solution
I think since at x=0 and t=0 , the displacement is equal to 1.2m, then we need to use y(x,t)=Acos(kx-wt) not y(x,t)=Asin(kx-wt) please tell me if this is true.
I got an answer for the displacement y(x,t)=y(2.6,8.60)=0,495m, using this formula: y(x,t)=Acos(kx-wt) but I am not sure if this is true. Please tell me if I am wrong and what should I do to fix it.
I found out that f=3.11Hz w=19.54 rad/s k=1.36