Physics

Problem

A plane longitudinal wave in air is given by

y_i = A \sin(\omega t - kx)

and moves towards the open end of a narrow pipe located at

x = 0

. Which expression can represent the wave reflected from the open end? a)

-A\sin(\omega t + kx)

A\sin(\omega t + kx)

A\sin(\omega t - kx)

A\sin(\omega t + kx + \dfrac{\pi}{2})