Direction of Travelling Waves

The two waves (y₁=y_m Sin(k x - w t) and y₂=y_m Sin(k x +w t)) above have the same amplitude, frequency and the speed, but travelling to the right and left directions respectively. Click above to change the speeds of waves keeping the wavelength (l) the same. Note that the frequency (w) of the wave changes (observe the oscillating particle) accordingly ( w=k v) to keep the same k (2p/l).