Open Source Ejs Newton's First Law java applet
Newton's First Law EJS applet by lookang
"A body continues to maintain its state of rest or of uniform motion unless acted upon by an external unbalanced force." This law is known as the law of inertia. http://en.wikipedia.org/wiki/Newton%27s_laws_of_motion
This has a lot of potential of students doing by modifying equations in EJS.
simple enough i hope!
PS: press "Enter" on the keyboard when keying in new values? The input field need to be white (registered by applet), if it is still yellow (unregistered), press "enter" on the keyboard