Here is the EJS version of the same applet.
The blue arrow represents the friction force, while red arrow is the velocity vector.
The red trace represents Vx as a function of time Vx(t), while green trace represents $R*\omega$ of the ping-pong ball.
When $R*\omega$ equal to Vx, the ping-pong  ball become rolling without slipping (And the slide friction disappear).

translate strings in simulation to different language format before download
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Press the Alt key and the left mouse button to drag the applet off the browser and onto the desktop. This work is licensed under a Creative Commons Attribution 2.5 Taiwan License
Download EJS jar file(1509kB):double click downloaded file to run it. (18 times by 9 users) , Download EJS source (10 times by 8 users) View EJS source