This paper shows how a freely downloadable and powerful software package, "SMath Studio," can be used to model physical systems in physics teaching. The software can form the basis of lecture demonstrations by teachers or can be used individually by students working in an educational environment or on their own home computers.

This paper has two parts. In the first part, intended for physics students as well as for engineering students whose primary interest is not physics, a new lesson related to shadow properties is given as a part of lectures on light. The effects resulting from a shadow 'motion' observed on a screen were looked into. The relationship between the…