3-5 Transverse waves on a string have wave speed 8.00 m/s, amplitude 0.070
m, and wavelength 0.320 m. The waves travel in the -x direction, and at t = 0
the x = 0 end of the string has its maximum upward displacement. (a) Find the
frequency and period of these waves. (b) Write a wave function describing the
wave. (c) Find the transverse displacement of a particle a x = 0.360 m at time
t = 0.150 s. (d) How much time must elapse from the instant in part (c) until
the particle at x = 0.360 m next has maximum upward displacement?
3-6 What is the non-zero minimum thickness for the air layer between two flat
glass surfaces if the glass is to appear bright when 640-nm light is incident
normally? What if the glass is to appear dark?
