In a longitudinal wave, the motion of the medium is parallel to the direction of the wave. This means that the particles move left and right which in turn makes the other particles start to oscillate.
The UNIA founded by Marcus Garvey has a constitution which defines red, black, and green as the Pan-African colours: red representing the noble blood that unites all people of African ancestry, the colour black for the people, green for the rich land of Africa..
The Symbolism of Colors. Color is all around us, present everywhere we turn, as constant as the air we breathe. Perhaps it is inevitable that human society will associate certain colors with different significant aspects of our lives. Different cultures all around the world each have their own meanings for the different colors, and within these cultures their meanings have also changed over time.