This is a set of three web-based labs for grades 7-9 relating to the energy of moving objects. In the first two labs, students use a virtual catapult to hurl objects of varying mass, from a pebble to a wrecking ball. Initial velocity can be changed with a slider. After each toss, a table is displayed showing the mass in kilograms, the speed in meters/second, and the energy in Joules. The activities are designed to clarify the relationships among mass, initial speed of object thrown, and energy. The final lab  introduces very small objects moving at high speeds: a paramecium, bacteria, virus, proton, and electron. The lab guides students to challenge their own thinking as they see that different rules seem to govern the movement of these tiny objects.

Editor's Note: Lab 3 is expected to create conflict in the student's mind about the concepts they just learned in Labs 1 and 2. Your students will actually be exploring Special Relativity, where the laws of Newtonian mechanics do not apply. Students who struggled with the concepts in Labs 1 and 2 may be unable to complete Lab 3 without extensive teacher intervention.

This item is part of a larger collection of interactive Java labs developed for use in middle school and high school.  See Related items on this page for a link to the full collection.

Please note that this resource requires Flash.