The disturbance shown in red color is due to a source somewhere beyond the left end. The disturbance shown in blue color is due to a source somewhere beyond the right end. The resultant disturbance is shown in yellow color. Check this applet too
The disturbance shown in red color is due to a source somewhere beyond the left end. The disturbance shown in blue color is due to a source somewhere beyond the right end. The resultant disturbance is shown in yellow color.
Check this applet too