The displacement of a point on a string is given (in centimetres) by
y(x,t)=5.0cos(0.5x−40t)
where x is in metres and t in seconds.
(i) Find the amplitude and the wavelength of the wave.
(ii) Calculate its frequency and time–period.
(iii) Determine the speed of the wave along the string.
(iv) Compute the instantaneous displacement of the point located at x=2m at the instant t=0.05s.