Question:
The displacement of a string is given by y(x,t) = 0.06 sin (2πx/3) cos (120πt) where x and y are in m and t in s. The length of the string is 1.5 m and its mass is 3.0 × 10-2kg.
(a) it represents a progressive wave of frequency 60 Hz
(b) it represents a stationary wave of frequency 60 Hz
(c) it is the result of the superposition of two waves of wavelength 3 m, frequency 60 Hz each travelling with a speed of 180 m/s in the opposite direction
(d) amplitude of this wave is constant
Solution:
The correct answers are
(b) it represents a stationary wave of frequency 60 Hz
(c) it is the result of the superposition of two waves of wavelength 3 m, frequency 60 Hz each travelling with a speed of 180 m/s in the opposite direction