Usage of real and virtual demonstrations by teaching physics in secondary school

Mokymas ir mokymasis – sudėtingas procesas, kurio sėkmė ir rezultatai priklauso nuo daugelio faktorių. Todėl ypač svarbus ugdymo turinio tobulinimas, racionalesnių mokymo metodų, būdų ir priemonių kūrimas. Šiuolaikinis mokymas vis labiau orientuojamas į ugdytinį, besirengiantį gyventi modernioje visuomenėje. Mokymo procesu siekiama kaip galima labiau sudominti ugdytinį mokomuoju dalyku, kelti jo pažintinius interesus. Interesas suprantamas kaip pastovus psichinis domėjimasis objektu, daiktu ar reiškiniu. Interesas iškyla kaip žmogaus dėmesio, minčių, sumanymų kryptingumas (Jovaiša, 1993). Pažintiniai interesai skatina mokinių loginį mąstymą, naujų, dar nežinomų dalykų ir jų priežastinių ryšių ieškojimą. Per pamoką mokinio interesai pasireiškia įvairiais būdais: aktyvumu, savarankiškumu atskleidžiant priežastinius ryšius ir dėsningumus, darant išvadas ir apibendrinant, atliekant bandymus ir t. t. J. Laužikas (1993) išskiria kelis domėjimosi pamoka atvejus: a) mokiniai susidomėję ir aktyvūs, b) domisi tik kai kuriais dalykais ir detalėmis, c) pasyvūs, abejingi, užduotis atlieka be susidomėjimo, d) mokinių interesai nesusiję su mokykline veikla. Tie patys mokiniai per vienas pamokas yra susidomėję ir aktyvūs, o per kitas pasyvūs. Taigi mokinių interesai priklauso ne tik nuo dalyko turinio, bet ir nuo mokymo būdo.Teaching means and methods that motivate pupils interest in particular subject has important significance to formation of pupils’ opinion on that subject. In order to motivate interest in subject it is crucial to find such methods that make pupils to be an active participant of learning process, but not a passive observer. Physics as a science has an unlimited potential to master new teaching methods and to educate cogitation of pupils. Demonstrational experiments are particularly suitable for that. Knowledge got during experiments are easy memorized and well memorable. Pupils gain desire to more actively study objects which are related to phenomena examined during demonstrations in physics. That is the main reason why demonstrational experiments develop interest in subject. In this paper three methods of how to perform demonstrational experiment are discussed while emphasizing positive and negative sides of these methods. Few different demonstrations for the study of the electromagnetic induction are presented in this article. Today demonstration in schools can be of three different kinds: real, virtual and interactive computer based real demonstrations. Three different kinds of demonstrations and their advantages and drawbacks are analyzed in the paper. Real demonstrations are when real devices and tools are used to perform it. Experiments during real demonstrations are visual and effective but sometimes are hard to observe the results. Because of that sometimes it is hard to fully explain observed phenomenon and to formulate the law. Virtual demonstrations are mathematical models of real physical system. During such demonstration we can observe visual processes, view plots. Because in virtual demonstration there is possibility to change certain parameters so it’s possible to see how certain variables affects the whole system and to analyze different aspect of the observed phenomenon. Also it is worth to mention that with virtual demonstrations it is possible to demonstrate such phenomena which are hard and costly to demonstrate during real experiments. However during virtual demonstrations pupils aren’t introduced to real tools and devices necessary to perform real experiment. In order to perform good virtual demonstrations teachers must have excellent mathematical modeling and information technology skills. Computer based real demonstrations are performed when together with real demonstrations data acquisition and representation are performed. In such demonstrations pupils observe live experiment and have possibility to change parameters, to view results which are processed by computer (plots, equations, mathematical analysis). Though, additional time is required for teachers to plan the demonstrations and to master the systems. If possessed at the cabinet of physics, data acquisition and representation together with real experiment are the best system for learning physics. Nevertheless real 77 and virtual systems, which enables to see and understand phenomena which with real devices it is difficult to demonstrate, are also necessary in the process of learning