A Simulation Based Virtual Laboratory design to learn and experiment the properties of elastic force by using the Superposition Principle is presented. To implement the laboratory experience it is made use of a JAVA simulation program that makes it independent of the computer platform. The support material for the experiment was built up: a short discussion of the involved concepts and the laboratory activities guide in the interactive engagement schema. A Learning Object was generated to implement the Virtual Lab, in order to get a reusable, with realities aspects represented and significant to the learning subject digital resource. Since it has to be a versatile and self contained resource to combine or integrate with other digital resources the Learning Object was developed following a versatile and repetitive pattern to include different laboratory experiences. The activities guide is included.