1. Astring π m long is started into motion by giving the middle one-half an initial velocity of 20 m/s. The string is stretched until the wave speed is 60 m/s. Determine the resulting displacement of the string as a function of x and t.
2. The right end of a 6-m-long wire, which is stretched until the wave speed is 60 m/s, is continually moved with the displacement 0.5 cos 4πt. What is the maximum amplitude of the resulting displacement?