Abstract: The Austrian Wuhan Doppler (1803-1853) revealed in a paper in 1842 [1] that the color of a luminous substance should change due to its relative movement and observer’s. This effect which is named Doppler Effect can be seen through all the waves, and Doppler himself impressed on its application in acoustic waves. In 1845 an empirical experiment was performed using a moving truck carrying few people blowing trumpets. In this paper, the Doppler Effect has been investigated for moving observer, source, and media while they are moving in a straight line with together, and moving with an angle between the sound wave and observer’s moving direction.Abstract: The Austrian Wuhan Doppler (1803-1853) revealed in a paper in 1842 [1] that the color of a luminous substance should change due to its relative movement and observer’s. This effect which is named Doppler Effect can be seen through all the waves, and Doppler himself impressed on its application in acoustic waves. In 1845 an empirical experiment was ...Show More