1. two harmonic waves which travel simultaneously along a wire are y, = 0.002 cos(8.0 x- 400 t) and y, = 0.002 cos(7.6 x - 380 t), where x and y are in meters,

1. Two harmonic waves which travel simultaneously along a wire are y, = 0.002 cos(8.0 x- 400 t) and y, = 0.002 cos(7.6 x - 380 t), where x and y are in meters, and t in sec. (a) What is the resultant wave and what are the phase and group velocities of the resultant wave? (b) Calculate the range Ax between the zeros of the group wave and find the product of Ax and Ak ?