Equipment for demonstrating Newton's third law and the energy conservation law in mechanics have successfully been constructed utilizing tine spherical plastic beads in place of metal ball bearings. To demonstrate Newton's third law, special magnetized Petri dishes were employed as objects, while to examine the energy conservation law, a large-angle frictionless slope (0 = 500) consisting of a thin plastic sheet on which the fine plastic beads were attached by the electrostatic force was employed. Using this method, a quantitative measurement of the energy conservation law was successfully carried out with a small error of less than 3%. A great advantage of this frictionless method is that we can use the same object (a Petri dish) to demonstrate many kinds of mechanics laws, such as the first, second and third laws of motion, the momentum conservation law, and the energy conservation law.

No abstract

No abstract

A new type of ammeter (PikoPiko) has been developed which indicates measured current by the movement of a spot of light and makes learners feel as if they were observing a visual image of electricity. The educational effect of this ammeter was investigated for 4th grade pupils in Japan. It was made clear that ordinary ammeters are good only for those who have grasped the correct concept of electricity and that PikoPiko can be a good tool to help pupils who have not yet mastered the correct concepts to understand electricity.