[b]Task[/b][br]Play the animation..[br][br]Change the Frequency f[sub]Q[/sub] of the source.[br]Change the velocity v[sub]Q[/sub] of the source.[br]Don't forget to turn on the [b]speakers[/b] and listen to the sound![br][br][i]Hint[/i]:[br]The sound lasts for 10 secunds in every repetition. After stopping the animation the sound might be hearable for some moments.[br]