Now, I see what you mean.
Here is another version.
Drag velocity arrow to change it's initial velocity.
Click init to reset to initial state.

Click the following image to view simulation.

/htdocs/ntnujava/ejsuser/2/users/ntnu/fkh/springfriction2_pkg/springfriction2.propertiesFull screen applet or Problem viewing java?Add to exception site list
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