Pulse Addition Applet Copyright B.E. Taylor, 1997, all rights reserved.

This applet will help you understand the Superposition Principle as it applies to two waves interacting on a string. The superposition principle states that the resulting wave from any number of waves interacting with each other is the algebraic sum of all of the waves at every instant. This means that the waves must be added together point by point for times of interest. This applet automates the addition of two waves for you.

The waves have identical shapes and speeds. One of fixed amplitude travels to the right. A second on of adjustable amplitude (full, half or zero and positive or negative) travels to the left. the controls for the applet are:

• Play - runs the entire 20 second animation. Cannot be stopped once started. Just wait!
• Step > - makes one step forward in time.
• Step >> - makes a large step (5 small steps) forward in time.
• < Step - makes one step backward in time.
• << Step - makes a large step backward in time.
• Reset - resets to the starting time and updates the shape of the waves to be superposed.

Radio Buttons - Select the amplitude of the adjustable wave. The fixed wave has an ampliutde of 2. Hence, 1 corresponds to a wave that is half as high as the original.

Questions or comments should be directed to:

Barney E. Taylor, Physics

Miami University - Hamilton

1601 Peck Blvd.

Hamilton, OH 45011

(513) 785-3223

taylorbe@miamioh.edu